Functional panel, display device, input/output device, and data processing device

ABSTRACT

A novel functional panel that is highly convenient or highly reliable is provided. The functional panel includes a first pixel. The first pixel includes a first element, a color conversion layer, and a first functional layer. The first functional layer is positioned between the first element and the color conversion layer. The first element has a function of emitting light and contains gallium nitride. The color conversion layer has a function of converting the color of light emitted from the first element into a different color. The first functional layer includes a first insulating film and a pixel circuit. The first insulating film includes a region positioned between the pixel circuit and the first element, and has an opening. The pixel circuit includes a first transistor. The first transistor includes a first oxide semiconductor film and is electrically connected to the first element through the opening.

BACKGROUND OF THE INVENTION 1. Field of the Invention

One embodiment of the present invention relates to a functional panel, adisplay device, an input/output device, a data processing device, or asemiconductor device.

Note that one embodiment of the present invention is not limited to theabove technical field. The technical field of one embodiment of theinvention disclosed in this specification and the like relates to anobject, a method, or a manufacturing method.

One embodiment of the present invention relates to a process, a machine,manufacture, or a composition of matter. Specific examples of thetechnical field of one embodiment of the present invention disclosed inthis specification include a semiconductor device, a display device, alight-emitting device, a power storage device, a memory device, a methodof driving any of them, and a method of manufacturing any of them.

2. Description of the Related Art

A display using a micro light-emitting diode whose chromaticity changeslittle with respect to a current density is known (Patent Document 1).Specifically, a plurality of pixels each include a display element and amicrocontroller. The microcontroller includes a first transistor, atriangular wave generation circuit, a comparator, a switch, and aconstant current circuit. The first transistor has a function ofretaining a potential corresponding to data written to the pixel bybeing turned off.

The triangular wave generation circuit has a function of generating atriangular wave signal. The comparator has a function of generating anoutput signal corresponding to the retained potential and the triangularwave signal. The switch has a function of controlling, in accordancewith the output signal, the supply of a current flowing through theconstant current circuit to the display element.

REFERENCE

-   [Patent Document 1] PCT International Publication No. WO2019/130138

SUMMARY OF THE INVENTION

An object of one embodiment of the present invention is to provide anovel functional panel that is highly convenient, useful, or reliable.Another object is to provide a novel display device that is highlyconvenient, useful, or reliable. Another object is to provide a novelinput/output device that is highly convenient, useful, or reliable.Another object is to provide a novel data processing device that ishighly convenient, useful, or reliable. Another object is to provide anovel functional panel, a novel display device, a novel input/outputdevice, a novel data processing device, or a novel semiconductor device.

Note that the descriptions of these objects do not preclude theexistence of other objects. One embodiment of the present invention doesnot have to achieve all these objects. Other objects will be apparentfrom and can be derived from the descriptions of the specification, thedrawings, the claims, and the like.

(1) One embodiment of the present invention is a functional panelincluding a first pixel. The first pixel includes a first element, acolor conversion layer, and a first functional layer.

The first functional layer is positioned between the first element andthe color conversion layer. The first element has a function of emittinglight and contains gallium nitride.

The color conversion layer has a function of converting the color oflight emitted from the first element into a different color.

The first functional layer includes a first insulating film and a pixelcircuit. The first insulating film includes a region positioned betweenthe pixel circuit and the first element, and has an opening.

The pixel circuit includes a first transistor. The first transistorincludes a first oxide semiconductor film and is electrically connectedto the first element through the opening.

(2) One embodiment of the present invention is a functional panelincluding the first pixel. The first pixel includes the first elementand the first functional layer.

The first element has a function of emitting light and includes a firstelectrode, a second electrode, and a layer containing a light-emittingmaterial. The layer containing a light-emitting material includes aregion positioned between the first electrode and the second electrode,and contains gallium nitride.

The first functional layer includes the first insulating film and thepixel circuit. The first insulating film includes a region positionedbetween the pixel circuit and the first element, and has the opening.

The pixel circuit includes the first transistor. The first transistorincludes the first oxide semiconductor film and is electricallyconnected to the first electrode through the opening.

Thus, the pixel circuit can be provided to overlap with the firstelement. Alternatively, the first element can occupy a larger area inthe first pixel. Alternatively, high luminance can be obtained at a lowdensity of current flowing through the first element. Alternatively, thereliability can be improved as compared to the case of using an organiccompound for the layer containing a light-emitting material.Alternatively, current leakage from the first transistor in an off statecan be reduced. Alternatively, the transistor can have less operationcharacteristics distribution, which can reduce display unevenness.Alternatively, the pixel circuit can have stable operationcharacteristics. As a result, a novel functional panel that is highlyconvenient, useful, or reliable can be provided.

(3) Another embodiment of the present invention is a functional panel inwhich the first insulating film includes a second insulating film and athird insulating film.

The second insulating film includes a region where the third insulatingfilm is positioned between the first transistor and the secondinsulating film, and contains silicon and oxygen. The third insulatingfilm contains silicon and nitrogen.

Accordingly, diffusion of impurities that cause malfunction during theoperation can be inhibited. Alternatively, diffusion of impurities suchas water and hydrogen into the first transistor can be inhibited. As aresult, a novel functional panel that is highly convenient, useful, orreliable can be provided.

(4) Another embodiment of the present invention is the functional panelincluding a pixel set.

The pixel set includes the first pixel and a second pixel, and thesecond pixel includes a second element.

The first insulating film includes a fourth insulating film, and thefourth insulating film has a function of separating the second elementfrom the first element.

Accordingly, an influence of the operation of the first element on theoperation of the second element can be reduced. Alternatively, thesecond element can be positioned close to the first element.Alternatively, the first element can occupy a larger area in the firstpixel and the second element can occupy a larger area in the secondpixel. As a result, a novel functional panel that is highly convenient,useful, or reliable can be provided.

(5) Another embodiment of the present invention is the functional panelincluding a first driver circuit.

The first functional layer includes the first driver circuit, and thefirst driver circuit includes a second transistor.

The second transistor includes a second oxide semiconductor film, andthe second oxide semiconductor film contains an element contained in thefirst oxide semiconductor film.

Thus, in a step of forming the semiconductor film of the transistorincluded in the pixel circuit, the semiconductor film of the transistorincluded in the first driver circuit can be formed. Alternatively, thefabrication process of the functional panel can be simplified. As aresult, a novel functional panel that is highly convenient, useful, orreliable can be provided.

(6) Another embodiment of the present invention is the functional panelfurther including a second functional layer.

The second functional layer includes a first contact, a second drivercircuit, and a fifth insulating film.

The first contact is electrically connected to the second drivercircuit, the second driver circuit includes a third transistor, and thethird transistor includes a semiconductor containing a Group 14 element.

The first functional layer includes a sixth insulating film and a secondcontact. The sixth insulating film includes a region positioned betweenthe fifth insulating film and the fourth insulating film, and includes aregion bonded to the fifth insulating film.

The second contact is electrically connected to the first contact andthe pixel circuit.

Accordingly, the second driver circuit can supply an image signal, forexample. Alternatively, a transistor including single crystal silicon asa semiconductor can be used for the second driver circuit, for example.Alternatively, the second driver circuit can be provided to overlap withthe first pixel, for example. Alternatively, the outer size of thefunctional panel can be reduced. As a result, a novel functional panelthat is highly convenient, useful, or reliable can be provided.

(7) Another embodiment of the present invention is the functional panelin which the second pixel has a function of performing display usinglight emitted from the second element.

The second element has a function of emitting light of the same color aslight emitted from the first element, the first pixel includes the colorconversion layer, and the color conversion layer has a function ofconverting the color of light emitted from the first element into adifferent color.

Accordingly, the second element can be formed in the same step as thefirst element. Alternatively, the first pixel can display a colordifferent from that of the second pixel. As a result, a novel functionalpanel that is highly convenient, useful, or reliable can be provided.

(8) Another embodiment of the present invention is the functional panelfurther including a region.

The region includes a group of pixel sets and another group of pixelsets.

The group of pixel sets is arranged in a row direction and includes thepixel set. The group of pixel sets is electrically connected to a firstconductive film.

Another group of pixel sets is arranged in a column directionintersecting the row direction, and includes the pixel set. The anothergroup of pixel sets is electrically connected to a second conductivefilm.

Thus, image data can be supplied to a plurality of pixels. As a result,a novel functional panel that is highly convenient, useful, or reliablecan be provided.

(9) Another embodiment of the present invention is a display deviceincluding a control unit and the functional panel.

The control unit is supplied with image data and control data, generatesdata on the basis of the image data, generates a control signal on thebasis of the control data, and supplies the data and the control signal.

The functional panel is supplied with the data and the control signal,and the pixel set performs display on the basis of the data.

Thus, image data can be displayed using the first display element. As aresult, a novel display device that is highly convenient, useful, orreliable can be provided.

(10) Another embodiment of the present invention is an input/outputdevice including an input unit and a display unit.

The display unit includes the above functional panel. The input unitincludes a sensing region and senses an object approaching the sensingregion. The sensing region includes a region overlapping with the pixelset.

Accordingly, an object that approaches the region overlapping with thedisplay unit can be sensed while image data is displayed using thedisplay unit. Alternatively, a finger or the like that approaches thedisplay unit can be used as a pointer to input positional data.Alternatively, positional data can be associated with image datadisplayed on the display unit. As a result, a novel input/output devicethat is highly convenient, useful, or reliable can be provided.

(11) Another embodiment of the present invention is a data processingdevice including an arithmetic device and an input/output device.

The arithmetic device is supplied with input data or sensing data,generates control data and image data on the basis of the input data orthe sensing data, and supplies the control data and the image data.

The input/output device supplies the input data and the sensing data, issupplied with the control data and the image data, and includes adisplay unit, an input unit, and a sensor unit.

The display unit includes the above functional panel and displays theimage data on the basis of the control data, and the input unitgenerates the input data. The sensor unit generates sensing data.

Accordingly, the control data can be generated on the basis of the inputdata or the sensing data. Alternatively, the image data can be displayedon the basis of the input data or the sensing data. As a result, a noveldata processing device that is highly convenient, useful, or reliablecan be provided.

(12) Another embodiment of the present invention is a data processingdevice including the functional panel and at least one of a keyboard, ahardware button, a pointing device, a touch sensor, an illuminancesensor, an imaging device, an audio input device, an eye-gaze inputdevice, and an attitude sensing device.

The above structure allows the arithmetic device to generate image dataor control data on the basis of data supplied using a variety of inputdevices. As a result, a novel data processing device that is highlyconvenient, useful, or reliable can be provided.

Although the block diagram attached to this specification showscomponents classified by their functions in independent blocks, it isdifficult to classify actual components according to their functionscompletely, and it is possible for one component to have a plurality offunctions.

In this specification, the terms “source” and “drain” of a transistorinterchange with each other depending on the polarity of the transistoror the levels of potentials applied to the terminals. In general, in ann-channel transistor, a terminal to which a lower potential is appliedis called a source, and a terminal to which a higher potential isapplied is called a drain. In a p-channel transistor, a terminal towhich a lower potential is applied is called a drain, and a terminal towhich a higher potential is applied is called a source. In thisspecification, the connection relation of a transistor is sometimesdescribed assuming for convenience that the source and the drain arefixed; in reality, the names of the source and the drain interchangewith each other depending on the relation of the potentials.

In this specification, a “source” of a transistor means a source regionthat is part of a semiconductor film functioning as an active layer or asource electrode connected to the semiconductor film. Similarly, a“drain” of a transistor means a drain region that is part of thesemiconductor film or a drain electrode connected to the semiconductorfilm. A “gate” means a gate electrode.

In this specification, a state in which transistors are connected toeach other in series means, for example, a state in which only one of asource and a drain of a first transistor is connected to only one of asource and a drain of a second transistor. In addition, a state in whichtransistors are connected in parallel means a state in which one of asource and a drain of a first transistor is connected to one of a sourceand a drain of a second transistor and the other of the source and thedrain of the first transistor is connected to the other of the sourceand the drain of the second transistor.

In this specification, the term “connection” means electrical connectionand corresponds to a state where current, voltage, or a potential can besupplied or transmitted. Accordingly, connection means not only directconnection but also indirect connection through a circuit element suchas a wiring, a resistor, a diode, or a transistor that allows current,voltage, or a potential to be supplied or transmitted.

In this specification, even when different components are connected toeach other in a circuit diagram, there is actually a case where oneconductive film has functions of a plurality of components, such as acase where part of a wiring serves as an electrode. The term“connection” in this specification also means such a case where oneconductive film has functions of a plurality of components.

In this specification, one of a first electrode and a second electrodeof a transistor refers to a source electrode and the other refers to adrain electrode.

According to one embodiment of the present invention, a novel functionalpanel that is highly convenient, useful, or reliable can be provided. Anovel display device that is highly convenient, useful, or reliable canbe provided. A novel input/output device that is highly convenient,useful, or reliable can be provided. A novel data processing device thatis highly convenient, useful, or reliable can be provided. A novelfunctional panel, a novel display device, a novel input/output device, anovel data processing device, or a novel semiconductor device can beprovided.

Note that the descriptions of these effects do not preclude theexistence of other effects. One embodiment of the present invention doesnot necessarily have all these effects. Other effects will be apparentfrom and can be derived from the descriptions of the specification, thedrawings, the claims, and the like.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIGS. 1A to 1C illustrate a structure of a functional panel of oneembodiment;

FIG. 2 is a top view illustrating a structure of a functional panel ofone embodiment;

FIG. 3 is a circuit diagram showing a configuration of a functionalpanel of one embodiment;

FIGS. 4A and 4B are cross-sectional views each illustrating a structureof a functional panel of one embodiment;

FIGS. 5A and 5B are cross-sectional views illustrating a structure of afunctional panel of one embodiment.

FIGS. 6A and 6B are cross-sectional views illustrating a structure of afunctional panel of one embodiment;

FIG. 7 illustrates a structure of a functional panel of one embodiment;

FIGS. 8A to 8D illustrate structures of display devices of embodiments;

FIG. 9 is a block diagram illustrating a structure of an input/outputdevice of one embodiment;

FIGS. 10A to 10C are a block diagram and projection views illustratingstructures of data processing devices of embodiments.

FIGS. 11A and 11B are flow charts showing a method for driving a dataprocessing device of one embodiment;

FIGS. 12A to 12C show a method for driving a data processing device ofone embodiment;

FIGS. 13A to 13E each illustrate a structure of a data processing deviceof one embodiment;

FIGS. 14A to 14E each illustrate a structure of a data processing deviceof one embodiment;

FIGS. 15A and 15B each illustrate a structure of a data processingdevice of one embodiment;

FIG. 16 illustrates a structure of a functional panel of one embodiment;

FIGS. 17A to 17C are cross-sectional views each illustrating a structureof a functional panel of one embodiment;

FIGS. 18A to 18C are cross-sectional views illustrating a structure of afunctional panel of one embodiment;

FIG. 19 illustrates a structure of a functional panel of one embodiment;

FIG. 20 is a cross-sectional view illustrating a structure of afunctional panel of one embodiment;

FIG. 21A is a top view of a semiconductor device of one embodiment ofthe present invention, and FIGS. 21B to 21D are cross-sectional views ofthe semiconductor device of one embodiment of the present invention;

FIG. 22A shows classification of IGZO crystal structures, FIG. 22B showsan XRD spectrum of a CAAC-IGZO film, and FIG. 22C shows a nanobeamelectron diffraction pattern of the CAAC-IGZO film;

FIGS. 23A and 23B are cross-sectional views illustrating a structure ofa functional panel of one embodiment; and

FIGS. 24A and 24B illustrate a structure example of an electronicdevice.

DETAILED DESCRIPTION OF THE INVENTION

The functional panel of one embodiment of the present invention includesthe first pixel, and the first pixel includes the first element, thecolor conversion layer, and the first functional layer. The firstfunctional layer is positioned between the first element and the colorconversion layer. The first element has a function of emitting light andcontains gallium nitride. The color conversion layer has a function ofconverting the color of light emitted from the first element into adifferent color. The first functional layer includes the firstinsulating film and the pixel circuit. The first insulating filmincludes a region positioned between the pixel circuit and the firstelement, and has the opening. The pixel circuit includes the firsttransistor. The first transistor includes the first oxide semiconductorfilm and is electrically connected to the first electrode through theopening.

Thus, the pixel circuit can be provided to overlap with the firstelement. The first element can occupy a larger area in the first pixel.High luminance can be obtained at a low density of current flowingthrough the first element. The reliability can be improved as comparedto the case of using an organic compound for the layer containing alight-emitting material. Current leakage from the first transistor in anoff state can be reduced. The transistor can have less operationcharacteristics distribution, which can reduce display unevenness. Thepixel circuit can have stable operation characteristics. As a result, anovel functional panel that is highly convenient, useful, or reliablecan be provided.

Embodiments will be described in detail with reference to the drawings.Note that the present invention is not limited to the followingdescription, and it will be readily appreciated by those skilled in theart that modes and details of the present invention can be modified invarious ways without departing from the spirit and scope of the presentinvention. Therefore, the present invention should not be construed asbeing limited to the description in the following embodiments. Note thatin structures of the present invention described below, the sameportions or portions having similar functions are denoted by the samereference numerals in different drawings, and the description thereof isnot repeated.

Embodiment 1

In this embodiment, structures of a functional panel of one embodimentof the present invention will be described with reference to FIGS. 1A to1C, FIG. 2, FIG. 3, FIGS. 4A and 4B, FIGS. 5A and 5B, and FIGS. 6A and6B.

FIG. 1A is a block diagram of the functional panel of one embodiment ofthe present invention, and FIGS. 1B and 1C each illustrate part of FIG.1A.

FIG. 2 illustrates a structure of the functional panel of one embodimentof the present invention, which is part of FIG. 1A.

FIG. 3 is a circuit diagram of a pixel circuit 530G(i,j) that can beused in the functional panel of one embodiment of the present invention.

FIG. 4A illustrates the structure of the functional panel of oneembodiment of the present invention, and illustrates a cross-section ofa pixel set 703(i,j) and cross sections along the cutting lines X1-X2,X3-X4, and X9-X10 in FIG. 1A. FIG. 4B illustrates a structure of thefunctional panel of one embodiment of the present invention, which isdifferent from of the structure in FIG. 4A.

FIG. 5A illustrates a structure of the functional panel of oneembodiment of the present invention and is a cross-sectional view of apixel 702G(i,j) illustrated in FIG. 1B. FIG. 5B is a cross-sectionalview illustrating part of FIG. 5A.

FIG. 6A illustrates a structure of the functional panel of oneembodiment of the present invention and is a cross-sectional view takenalong the cutting lines X1-X2 and X3-X4 in FIG. 1A. FIG. 6B illustratespart of FIG. 6A.

Note that in this specification, an integer variable of 1 or more may beused for reference numerals. For example, “(p)” where p is an integervariable of 1 or more may be used for part of a reference numeral thatspecifies any one of components (p components at a maximum). For anotherexample, “(m,n)” where each of m and n is an integer variable of 1 ormore may be used for part of a reference numeral that specifies any oneof components (m×n components at a maximum).

<Structure Example 1 of Functional Panel 700>

A functional panel 700 described in this embodiment includes the pixel702G(i,j) (see FIGS. 1A and 1).

<<Structure Example 1 of Pixel 702G(i,j)>>

The pixel 702G(i,j) includes an element 550G(i,j) and a functional layer520 (see FIG. 1C and FIG. 5A).

<<Structure Example 1 of Element 550G(i,j)>>

The element 550G(i,j) has a function of emitting light, and includes anelectrode 551(i,j), an electrode 552, and a layer 553 containing alight-emitting material (see FIG. 5A). For example, a light-emittingdiode can be used as the element 550G(i,j). Specifically, a verticallight-emitting diode can be used as the element 550G(i,j). In addition,a light-emitting diode that emits blue light can be used as the element550G(i,j).

The layer 553 containing a light-emitting material includes a regionpositioned between the electrode 551(i,j) and the electrode 552, andcontains gallium nitride.

<<Structure Example 1 of Functional Layer 520>>

The functional layer 520 includes an insulating film 501 and a pixelcircuit 530G(i,j) (see FIGS. 4A and 4B and FIG. 5A). The functionallayer 520 includes, for example, a transistor M21 used in the pixelcircuit 530G(i,j) (see FIG. 3 and FIG. 5A).

<<Structure Example 1 of Insulating Film 501>>

The insulating film 501 includes a region positioned between the pixelcircuit 530G(i,j) and the element 550G(i,j), and has an opening591G(i,j).

<<Structure Example of Pixel Circuit 530G(i,j)>>

The pixel circuit 530G(i,j) includes the transistor M21 (see FIG. 3 andFIG. 5A). The transistor M21 is electrically connected to the electrode551(i,j) through the opening 591G. Note that the transistor M21 includesan oxide semiconductor film. A conductive film 512A electricallyconnects the transistor M21 and the electrode 551(i,j), for example. Inaddition, a conductive film 512B electrically connects the transistorM21 and a conductive film ANO (see FIG. 3).

Thus, the pixel circuit 530G(i,j) can be provided to overlap with theelement 550G(i,j). The element 550G(i,j) can occupy a larger area in thepixel 702G(i,j). High luminance can be obtained at a low density ofcurrent flowing through the element 550G(i,j). The reliability can beimproved as compared to the case of using an organic compound for thelayer 553 containing a light-emitting material. Current leakage from thetransistor M21 in an off state can be reduced. The transistor can haveless operation characteristics distribution, which can reduce displayunevenness. The pixel circuit 530G(i,j) can have stable operationcharacteristics. As a result, a novel functional panel that is highlyconvenient, useful, or reliable can be provided.

<<Structure Example 2 of Insulating Film 501>>

The insulating film 501 includes an insulating film 501B and aninsulating film 501C. The insulating film 501B includes a region wherethe insulating film 501C is positioned between the transistor M21 andthe insulating film 501B, and contains silicon and oxygen. Theinsulating film 501C contains silicon and nitrogen.

Accordingly, diffusion of impurities that cause malfunction during theoperation into the transistor M21 can be inhibited. Alternatively,diffusion of impurities such as water and hydrogen into the transistorM21 can be inhibited. As a result, a novel functional panel that ishighly convenient, useful, or reliable can be provided.

<Structure Example 2 of Functional Panel 700>

The functional panel described in this embodiment includes a pixel set703(i,j).

<<Structure Example 1 of Pixel Set 703(i,j)>>

The pixel set 703(i,j) includes the pixel 702G(i,j) and a pixel702B(i,j) (see FIG. 1i ). The pixel 702B(i,j) includes an element550B(i,j).

The insulating film 501 includes an insulating film 501A, and theinsulating film 501A has a function of isolating the element 550B(i,j)from the element 550G(i,j) (see FIG. 5A). Specifically, the insulatingfilm 501A has a function of isolating light-emitting layers 553EMbetween adjacent elements.

Accordingly, an influence of the operation of the element 550G(i,j) onthe operation of the element 550B(i,j) can be reduced. Specifically, acrosstalk phenomenon in which the element 550B(i,j) is unintentionallyoperated in accordance with the operation of the element 550G(i,j) canbe inhibited. Alternatively, the element 550B(i,j) can be positionedclose to the element 550G(i,j). Alternatively, the element 550G(i,j) canoccupy a larger area in the pixel 702G(i,j) and the element 550B(i,j)can occupy a larger area in the pixel 702B(i,j). Furthermore, theaperture ratio of the pixel 702G(i,j) can be increased. As a result, anovel functional panel that is highly convenient, useful, or reliablecan be provided.

The functional panel 700 includes a conductive film G1(i), a conductivefilm G2(i), a conductive film S1 g(j), a conductive film S2 g(j), theconductive film ANO, and a conductive film VCOM2 (see FIG. 3).

The conductive film G(i) is supplied with a first selection signal, theconductive film G2(i) is supplied with a second selection signal, theconductive film S1 g(j) is supplied with an image signal, and theconductive film S2 g(j) is supplied with a control signal, for example.

<<Structure Example 2 of Pixel Set 703(i,j)>>

The pixel set 703(i,j) includes the pixel 702G(i,j) (see FIG. 1). Thepixel 702G(i,j) includes the pixel circuit 530G(i,j) and the element550G(i,j) (see FIG. 1C).

<<Structure Example 1 of Pixel Circuit 530G(i,j)>>

The pixel circuit 530G(i,j) is supplied with the first selection signaland obtains an image signal in accordance with the first selectionsignal. For example, the first selection signal can be supplied usingthe conductive film G1(i) (see FIG. 3). The image signal can be suppliedusing the conductive film S1 g(j). Note that the operation of supplyingthe first selection signal and making the pixel circuit 530G(i,j) obtainan image signal can be referred to as “writing”.

<<Structure Example 2 of Pixel Circuit 530G(i,j)>>

The pixel circuit 530G(i,j) includes a switch SW21, a switch SW22, thetransistor M21, a capacitor C21, and a node N21 (see FIG. 3). The pixelcircuit 530G(i,j) includes a node N22, a capacitor C22, and a switchSW23.

The transistor M21 includes a gate electrode electrically connected tothe node N21, the first electrode electrically connected to the element550G(i,j), and the second electrode electrically connected to theconductive film ANO.

The switch SW21 includes a first terminal electrically connected to thenode N21 and a second terminal electrically connected to the conductivefilm Slg(j), and has a function of controlling its on/off state on thebasis of the potential of the conductive film G1(i).

The switch SW22 includes a first terminal electrically connected to theconductive film S2 g(j), and has a function of controlling its on/offstate on the basis of the potential of the conductive film G2(i).

The capacitor C21 includes a conductive film electrically connected tothe node N21 and a conductive film electrically connected to a secondelectrode of the switch SW22.

Accordingly, an image signal can be stored in the node N21.Alternatively, the potential of the node N21 can be changed using theswitch SW22. Alternatively, the intensity of light emitted from theelement 550G(i,j) can be controlled with the potential of the node N21.As a result, a novel functional panel that is highly convenient orreliable is provided.

<<Structure Example 1 of Element 550G(i,j)>>

The element 550G(i,j) is electrically connected to the pixel circuit530G(i,j) (see FIG. 2 and FIG. 3). The element 550G(i,j) includes theelectrode 551G(i,j) electrically connected to the pixel circuit530G(i,j), and the electrode 552 electrically connected to theconductive film VCOM2 (see FIG. 3 and FIG. 5A). Note that the element550G(i,j) has a function of operating on the basis of the potential ofthe node N21.

Instead of the light-emitting diode, for example, an organicelectroluminescent element or a quantum dot LED (QDLED) can be used asthe element 550G(i,j).

<<Structure Example 3 of Pixel Set 703(i,j)>>

A plurality of pixels can be used in the pixel set 703(i,j). Forexample, a plurality of pixels that show colors of different hues can beused. Note that a plurality of pixels can be referred to as subpixels.In addition, a set of subpixels can be referred to as a pixel.

Such a structure enables additive mixture of colors shown by theplurality of pixels. Alternatively, it is possible to express a color ofa hue that an individual pixel cannot show.

Specifically, the pixel 702B(i,j) for showing blue, the pixel 702G(i,j)for showing green, and a pixel 702R(i,j) for showing red can be used inthe pixel set 703(i,j). The pixel 702B(i,j), the pixel 702G(i,j), andthe pixel 702R(i,j) can each be referred to as a subpixel (see FIG. 1).

As another example, a pixel for showing white or the like in addition tothe above set can be used in the pixel set 703(i,j). Moreover, a pixelfor showing cyan, a pixel for showing magenta, and a pixel for showingyellow can be used in the pixel set 703(i,j).

As another example, a pixel emitting infrared rays in addition to theabove set can be used in the pixel set 703(i,j). Specifically, a pixelthat emits light including light with a wavelength of greater than orequal to 650 nm and less than or equal to 1000 nm can be used in thepixel set 703(i,j).

<Structure Example 3 of Functional Panel 700>

The functional panel described in this embodiment includes the drivercircuit GD (see FIG. 1A). In addition, a driver circuit SD is included.

<<Structure Example of Driver Circuit GD>>

The driver circuit GD has a function of supplying the first selectionsignal and the second selection signal. For example, the driver circuitGD is electrically connected to the conductive film G1(i) to supply thefirst selection signal, and is electrically connected to the conductivefilm G2(i) to supply the second selection signal.

<<Structure Example of Driver Circuit SD>>

The driver circuit SD has a function of supplying the image signal andthe control signal, and the control signal includes a first level and asecond level. The driver circuit SD is electrically connected to theconductive film Slg(j) to supply the image signal, and is electricallyconnected to the conductive film S2 g(j) to supply the control signal,for example.

<<Structure Example 2 of Functional Layer 520>>

The functional layer 520 includes the driver circuit GD (see FIGS. 4Aand 4B and FIG. 6A). The functional layer 520 includes, for example, atransistor MD used in the driver circuit GD.

<<Structure Example 1 of Driver Circuit GD>>

The driver circuit GD includes the transistor MD, the transistor MDincludes an oxide semiconductor film, and the oxide semiconductor filmcontains an element contained in the oxide semiconductor film of thetransistor M21.

A semiconductor film with the same composition as the semiconductor filmused for the transistor M21 can be used for the transistor MD, forexample.

Thus, in the step of forming the semiconductor film of the transistorincluded in the pixel circuit 530G(i,j), the semiconductor film of thetransistor included in the driver circuit GD can be formed.Alternatively, the fabrication process of the functional panel can besimplified. As a result, a novel functional panel that is highlyconvenient, useful, or reliable can be provided.

<<Structure Example of Transistor>>

A bottom-gate transistor, a top-gate transistor, or the like can be usedin the functional layer 520. Specifically, a transistor can be used as aswitch.

The transistor includes a semiconductor film 508, a conductive film 504,a conductive film 507A, and a conductive film 507B (see FIG. 5B).

The semiconductor film 508 includes a region 508A electrically connectedto the conductive film 507A and a region 508B electrically connected tothe conductive film 507B. The semiconductor film 508 includes a region508C between the region 508A and the region 508B.

The conductive film 504 includes a region overlapping with the region508C and has a function of a gate electrode.

An insulating film 506 includes a region positioned between thesemiconductor film 508 and the conductive film 504. The insulating film506 has a function of a gate insulating film.

The conductive film 507A has one of a function of a source electrode anda function of a drain electrode, and the conductive film 507B has theother.

A conductive film 524 can be used in the transistor. The conductive film524 includes a region where the semiconductor film 508 is positionedbetween the conductive film 504 and the conductive film 524. Theconductive film 524 has a functions of a second gate electrode.

Note that in a step of forming the semiconductor film used in thetransistor of the pixel circuit, the semiconductor film used in thetransistor of the driver circuit can be formed.

<<Structure Example 1 of Semiconductor Film 508>>

For example, a semiconductor containing a Group 14 element can be usedfor the semiconductor film 508. Specifically, a semiconductor containingsilicon can be used for the semiconductor film 508.

[Hydrogenated Amorphous Silicon]

For example, hydrogenated amorphous silicon can be used for thesemiconductor film 508. Microcrystalline silicon or the like can also beused for the semiconductor film 508. Thus, it is possible to provide afunctional panel having less display unevenness than a functional panelusing polysilicon for the semiconductor film 508, for example.Alternatively, the size of the functional panel can be easily increased.

[Polysilicon]

For example, polysilicon can be used for the semiconductor film 508. Inthis case, for example, the field-effect mobility of the transistor canbe higher than that of a transistor using hydrogenated amorphous siliconfor the semiconductor film 508. For another example, the drivingcapability can be higher than that of a transistor using hydrogenatedamorphous silicon for the semiconductor film 508. For another example,the aperture ratio of the pixel can be higher than that of a transistorusing hydrogenated amorphous silicon for the semiconductor film 508.

For another example, the reliability of the transistor can be higherthan that of a transistor using hydrogenated amorphous silicon for thesemiconductor film 508.

The temperature required for fabricating the transistor can be lowerthan that required for a transistor using single crystal silicon, forexample.

The semiconductor film used in the transistor of the driver circuit canbe formed in the same step as the semiconductor film used in thetransistor of the pixel circuit. Alternatively, the driver circuit canbe formed over a substrate where the pixel circuit is formed.Alternatively, the number of components included in an electronic devicecan be reduced.

<<Structure Example 2 of Semiconductor Film 508>>

For example, a metal oxide can be used for the semiconductor film 508.In this case, the pixel circuit can hold an image signal for a longertime than a pixel circuit including a transistor that uses amorphoussilicon for the semiconductor film. Specifically, a selection signal canbe supplied at a frequency of lower than 30 Hz, preferably lower than 1Hz, further preferably less than once per minute while flickering issuppressed. Consequently, fatigue of a user of the data processingdevice can be reduced. Furthermore, power consumption for driving can bereduced.

Alternatively, a functional panel having less display unevenness than afunctional panel using polysilicon for the semiconductor film 508, forexample, can be provided. Alternatively, the element 550G(i,j) can bedriven at a duty ratio of 50% or lower. For another example, smartglasses or a head mounted display can be provided.

For example, a transistor using an oxide semiconductor can be used.Specifically, an oxide semiconductor containing indium, an oxidesemiconductor containing indium, gallium, and zinc, or an oxidesemiconductor containing indium, gallium, zinc, and tin can be used forthe semiconductor film.

For example, a transistor having a lower leakage current in an off statethan a transistor using amorphous silicon for a semiconductor film canbe used. Specifically, a transistor using an oxide semiconductor for asemiconductor film can be used as a switch or the like. In that case,the potential of the floating node can be held for a longer time than ina circuit in which a transistor using amorphous silicon is used as aswitch.

For example, a 25-nm-thick film including indium, gallium, and zinc canbe used as the semiconductor film 508.

Thus, flicker of display can be suppressed. Alternatively, powerconsumption can be reduced. A moving image that moves fast can bedisplayed smoothly. A photograph and the like can be displayed in alarge number of gray levels. As a result, a novel functional panel thatis highly convenient, useful, or reliable can be provided.

<<Structure Example 3 of Semiconductor Film 508>>

For example, a compound semiconductor can be used as a semiconductor ofthe transistor. Specifically, a semiconductor containing galliumarsenide can be used.

For example, an organic semiconductor can be used as a semiconductor ofthe transistor. Specifically, an organic semiconductor containing any ofpolyacenes or graphene can be used for the semiconductor film.

<<Structure Example of Capacitor>>

The capacitor includes one conductive film, another conductive film, andan insulating film. The insulating film includes a region positionedbetween these conductive films.

For example, the capacitor can include a conductive film used as thesource electrode or the drain electrode of the transistor, a conductivefilm used as the gate electrode, and an insulating film used as the gateinsulating film.

<<Structure Example 2 of Functional Layer 520>>

The functional layer 520 includes an insulating film 521, an insulatingfilm 518, an insulating film 516, the insulating film 506, an insulatingfilm 501C, and the like (see FIGS. 5A and 5B).

The insulating film 521 includes a region where the pixel circuit530G(i,j) is positioned between the element 550G(i,j) and the insulatingfilm 521.

The insulating film 518 includes a region positioned between theinsulating film 521 and the insulating film 501C.

The insulating film 516 includes a region positioned between theinsulating film 518 and the insulating film 501C.

The insulating film 506 includes a region positioned between theinsulating film 516 and the insulating film 501C.

[Insulating Film 521]

For example, an insulating inorganic material, an insulating organicmaterial, or an insulating composite material including an inorganicmaterial and an organic material can be used for the insulating film521.

Specifically, an inorganic oxide film, an inorganic nitride film, aninorganic oxynitride film, and the like, or a layered material obtainedby stacking some of these films can be used for the insulating film 521.

For example, a film including any of a silicon oxide film, a siliconnitride film, a silicon oxynitride film, an aluminum oxide film, and thelike, or a film including a material obtained by stacking any of thesefilms can be used for the insulating film 521. Note that a siliconnitride film is a dense film and has an excellent function of inhibitingdiffusion of impurities.

For example, polyimide, polysiloxane, a composite material of aninorganic material and polyimide or polysiloxane, or the like can beused for the insulating film 521. Note that polyimide is excellent inthe following properties, for example, compared with other organicmaterials: thermal stability, an insulating property, toughness, a lowdielectric constant, a low coefficient of thermal expansion, and highchemical resistance. Accordingly, in particular, polyimide can besuitably used for the insulating film 521 or the like. However, oneembodiment of the present invention is not limited thereto. For example,for the insulating film 521, an inorganic material such as siliconoxide, silicon nitride, or aluminum oxide may be used. The use of aninorganic material for the insulating film 521 can improve thereliability of the transistor M21.

Alternatively, the insulating film 521 may be formed using aphotosensitive material. Specifically, a film formed usingphotosensitive polyimide, a photosensitive acrylic resin, or the likecan be used as the insulating film 521.

Thus, steps due to various components overlapping with the insulatingfilm 521, for example, can be reduced. The insulating film 521 may havea stacked-layer structure of any of the above-described inorganicmaterials and an organic material having a planarization function, suchas a polyimide or photosensitive acrylic resin.

[Insulating Film 518]

For example, a material that can be used for the insulating film 521 canbe used for the insulating film 518.

For example, a material that has a function of inhibiting diffusion ofoxygen, hydrogen, water, alkali metal, alkaline earth metal, and thelike can be used for the insulating film 518. Specifically, a nitrideinsulating film can be used as the insulating film 518. For example,silicon nitride, silicon nitride oxide, aluminum nitride, aluminumnitride oxide, or the like can be used for the insulating film 518.Thus, diffusion of impurities into the semiconductor film of thetransistor can be inhibited.

[Insulating Film 516]

For example, a material that can be used for the insulating film 521 canbe used for the insulating film 516.

Specifically, a film formed by a method different from a method offorming the insulating film 518 can be used as the insulating film 516.

[Insulating Film 506]

For example, a material that can be used for the insulating film 521 canbe used for the insulating film 506.

Specifically, a film including a silicon oxide film, a siliconoxynitride film, a silicon nitride oxide film, a silicon nitride film,an aluminum oxide film, a hafnium oxide film, an yttrium oxide film, azirconium oxide film, a gallium oxide film, a tantalum oxide film, amagnesium oxide film, a lanthanum oxide film, a cerium oxide film, or aneodymium oxide film can be used as the insulating film 506.

[Insulating Film 501D]

An insulating film 501D includes a region positioned between theinsulating film 501C and the insulating film 516.

For example, a material that can be used for the insulating film 506 canbe used for the insulating film 501D.

[Insulating Film 501C]

For example, a material that can be used for the insulating film 521 canbe used for the insulating film 501C. Specifically, a materialcontaining silicon and oxygen can be used for the insulating film 501C.Thus, diffusion of impurities into the pixel circuit, the element550G(i,j), or the like can be inhibited.

<<Structure Example 3 of Functional Layer 520>>

The functional layer 520 includes a conductive film, a wiring, and aterminal. A conductive material can be used for the wiring, theelectrode, the terminal, the conductive film, and the like.

[Wiring and the Like]

For example, an inorganic conductive material, an organic conductivematerial, a metal, conductive ceramics, or the like can be used for thewiring and the like.

Specifically, for example, a metal element selected from aluminum, gold,platinum, silver, copper, chromium, tantalum, titanium, molybdenum,tungsten, nickel, iron, cobalt, palladium, and manganese can be used forthe wiring and the like. Alternatively, an alloy including any of theabove-described metal elements, or the like can be used for the wiringand the like. In particular, an alloy of copper and manganese issuitably used in microfabrication using a wet etching method.

Specifically, the wiring and the like can employ any of the followingstructures, for example: a two-layer structure in which a titanium filmis stacked over an aluminum film; a two-layer structure in which atitanium film is stacked over a titanium nitride film; a two-layerstructure in which a tungsten film is stacked over a titanium nitridefilm; a two-layer structure in which a tungsten film is stacked over atantalum nitride film or a tungsten nitride film; and a three-layerstructure in which a titanium film, an aluminum film, and a titaniumfilm are stacked in this order.

Specifically, a conductive oxide such as indium oxide, indium tin oxide,indium zinc oxide, zinc oxide, or zinc oxide to which gallium is addedcan be used for the wiring and the like.

Specifically, a film containing graphene or graphite can be used for thewiring and the like.

For example, a film containing graphene oxide is formed and is subjectedto reduction, so that a film containing graphene can be formed. As areducing method, a method with application of heat, a method using areducing agent, or the like can be employed.

For example, a film containing a metal nanowire can be used for thewiring and the like. Specifically, a nanowire containing silver can beused.

Specifically, a conductive polymer can be used for the wiring and thelike.

For example, a terminal 519B can be electrically connected to a flexibleprinted circuit FPC1 with the use of a conductive material (see FIGS. 4Aand 4B). Specifically, the terminal 519B can be electrically connectedto the flexible printed circuit FPC1 with the use of a conductivematerial CP.

<Structure Example 4 of Functional Panel 700>

The functional panel 700 includes a base 510, a base 770, and thesealant 705 (see FIG. 5A). The functional panel 700 also includes acomponent KB.

<<Base 510 and Base 770>>

A light-transmitting material can be used for the base 510 or the base770.

For example, a flexible material can be used for the base 510 or thebase 770. Thus, a functional panel having flexibility can be provided.

For example, a material with a thickness greater than or equal to 0.1 mmand less than or equal to 0.7 mm can be used. Specifically, a materialpolished to a thickness of approximately 0.1 mm can be used. As aresult, the base 510 or the base 770 can be lightweight.

A glass substrate having any of the following sizes, for example, can beused as the base 510 or the base 770: the 6th generation (1500 mm×1850mm), the 7th generation (1870 mm×2200 mm), the 8th generation (2200mm×2400 mm), the 9th generation (2400 mm×2800 mm), and the 10thgeneration (2950 mm×3400 mm). Thus, a large-sized display device can befabricated.

For the base 510 or the base 770, an organic material, an inorganicmaterial, a composite material of an organic material and an inorganicmaterial, or the like can be used.

For example, an inorganic material such as glass, ceramic, or metal canbe used. Specifically, non-alkali glass, soda-lime glass, potash glass,crystal glass, aluminosilicate glass, tempered glass, chemicallytempered glass, quartz, sapphire, or the like can be used for the base510 or the base 770. Alternatively, aluminosilicate glass, temperedglass, chemically tempered glass, sapphire, or the like can be favorablyused for the base 510 or the base 770 that is on the side closer to auser of the functional panel. This can prevent breakage or damage of thefunctional panel caused by the use.

Specifically, an inorganic oxide film, an inorganic nitride film, aninorganic oxynitride film, or the like can be used. For example, asilicon oxide film, a silicon nitride film, a silicon oxynitride film,or an aluminum oxide film can be used. Stainless steel, aluminum, or thelike can be used for the base 510 or the base 770.

For example, a single crystal semiconductor substrate or apolycrystalline semiconductor substrate made of silicon or siliconcarbide, a compound semiconductor substrate made of silicon germanium orthe like, or an SOI substrate can be used as the base 510 or the base770. Thus, a semiconductor element can be formed over the base 510 orthe base 770.

For example, an organic material such as a resin, a resin film, orplastic can be used for the base 510 or the base 770. Specifically, amaterial containing polyester, polyolefin, polyamide (e.g., nylon oraramid), polyimide, polycarbonate, polyurethane, an acrylic resin, anepoxy resin, or a resin having a siloxane bond, such as silicone, can beused for the base 510 or the base 770. For example, a resin film, aresin plate, a layered material, or the like containing any of thesematerials can be used. As a result, the base 510 or the base 770 can belightweight. Alternatively, for example, the functional panel can beless likely to suffer from damage by dropping or the like.

Specifically, polyethylene terephthalate (PET), polyethylene naphthalate(PEN), polyethersulfone (PES), a cyclic olefin polymer (COP), a cyclicolefin copolymer (COC), or the like can be used for the base 510 or thebase 770.

For example, a composite material formed by attaching a metal plate, athin glass plate, or a film of an inorganic material or the like and aresin film or the like can be used for the base 510 or the base 770. Forexample, a composite material formed by dispersing a fibrous orparticulate metal, glass, inorganic material, or the like into a resincan be used for the base 510 or the base 770. For example, a compositematerial formed by dispersing a fibrous or particulate resin, organicmaterial, or the like into an inorganic material can be used for thebase 510 or the base 770.

Furthermore, a single-layer material or a material in which a pluralityof layers are stacked can be used for the base 510 or the base 770. Forexample, a material in which insulating films and the like are stackedcan be used. Specifically, a material in which one or more filmsselected from a silicon oxide layer, a silicon nitride layer, a siliconoxynitride layer, and the like are stacked can be used. Thus, diffusionof impurities contained in the base can be prevented, for example.Alternatively, diffusion of impurities contained in glass or a resin canbe prevented. Alternatively, diffusion of impurities that pass through aresin can be prevented.

Alternatively, paper, wood, or the like can be used for the base 510 orthe base 770.

For example, a material having heat resistance high enough to withstandheat treatment in the fabrication process can be used for the base 510or the base 770. Specifically, a material that is resistant to heatapplied in the process of forming the transistor, the capacitor, and thelike directly on the base can be used for the base 510 or the base 770.

For example, it is possible to employ a method in which an insulatingfilm, a transistor, a capacitor, and the like are formed over a processsubstrate that is resistant to heat applied in the fabrication process,and then the formed components are transferred to the base 510 or thebase 770, for example. Thus, the insulating film, the transistor, thecapacitor, and the like can be formed over a flexible substrate, forexample.

<<Sealant>>

The sealant 705 includes a region positioned between the functionallayer 520 and the base 770, and has a function of bonding the functionallayer 520 and the base 770 together (see FIG. 5A). A sealant 505includes a region positioned between the functional layer 520 and thebase 510, and has a function of attaching the functional layer 520 andthe base 510 to each other.

For the sealant 705 and the sealant 505, an inorganic material, anorganic material, a composite material of an inorganic material and anorganic material, or the like can be used.

For example, an organic material such as a thermally fusible resin or acurable resin can be used for the sealant 705 and the sealant 505.

For example, an organic material such as a reactive curable adhesive, alight curable adhesive, a thermosetting adhesive, and/or an anaerobicadhesive can be used for the sealant 705 and the sealant 505.

Specifically, an adhesive containing an epoxy resin, an acrylic resin, asilicone resin, a phenol resin, a polyimide resin, an imide resin, apolyvinyl chloride (PVC) resin, a polyvinyl butyral (PVB) resin, or anethylene vinyl acetate (EVA) resin can be used as the sealant 705 andthe sealant 505.

<<Component KB>>

The component KB includes a region positioned between the functionallayer 520 and the base 770. The component KB has a function of providinga certain space between the functional layer 520 and the base 770.

<Fabrication Method of Functional Panel 700>

The fabrication method of the functional panel 700 includes thefollowing 18 steps.

In a first step, an n-type clad layer 553N is formed over a sapphiresubstrate, for example.

In a second step, the light-emitting layer 553EM is formed to overlapwith the n-type clad layer 553N.

In a third step, a p-type clad layer 553P is formed to overlap with thelight-emitting layer 553EM.

In a fourth step, the electrode 551(i,j) is formed to overlap with thep-type clad layer 553P.

In a fifth step, the electrode 551(i,j), the p-type clad layer 553P, andthe light-emitting layer 553EM are processed to have a predeterminedshape by an etching method.

In a sixth step, the insulating film 501A is formed to cover theelectrode 551(i,j).

In a seventh step, the insulating film 501A is processed to have apredetermined shape by a chemical polishing method, for example.

In an eighth step, the insulating film 501B is formed over theinsulating film 501A.

In a ninth step, the insulating film 501C is formed over the insulatingfilm 501B.

In a tenth step, the transistor M21 and the insulating film 516 areformed over the insulating film 501C.

In an eleventh step, an opening including the opening 591G is formed byan etching method.

In a twelfth step, the transistor M21 and the electrode 551(i,j) aremade to be electrically connected to each other.

In a thirteenth step, the insulating film 518 and the insulating film521 are formed over the transistor M21.

In a fourteenth step, the base 510 and the insulating film 521 areattached to each other with the sealant 505.

In a fifteenth step, the sapphire substrate, for example, is separatedfrom the n-type clad layer 553N. Note that in the fifteenth step, alaser lift-off method can be used, for example.

In a sixteenth step, the electrode 552 is formed to overlap with then-type clad layer 553N.

In a seventeenth step, the color conversion layer CC(G) is formed sothat the electrode 552 is positioned between the coloring layer CC(G)and the light-emitting layer 553EM.

In an eighteenth step, the base 770 and the color conversion layer CC(G)are attached to each other with the sealant 705.

<Structure Example 5 of Functional Panel 700>

The functional panel 700 described in this embodiment includes the pixel702G(i,j) (see FIG. 4B and FIG. 23A).

<<Structure Example 1 of Pixel 702G(i,j)>>

The pixel 702G(i,j) includes the element 550G(i,j), the color conversionlayer CC(G), and the functional layer 520 (see FIG. 23A).

<<Structure Example 1 of Element 550G(i,j)>>

The functional layer 520 is positioned between the color conversionlayer CC(G) and the element 550G(i,j). The element 550G(i,j) has afunction of emitting light and contains gallium nitride.

For example, a light-emitting diode can be used as the element550G(i,j). Specifically, a vertical light-emitting diode can be used asthe element 550G(i,j). In addition, a light-emitting diode that emitsblue light can be used as the element 550G(i,j). Note that the n-typeclad layer 553N has conductivity. Thus, the n-type clad layer 553N canelectrically connect the element 550G(i,j) and an adjacent element,e.g., the element 550B(i,j). In other words, the n-type clad layer 553Nalso functions as an electrode.

<<Structure Example 1 of Color Conversion Layer CC(G)>>

The color conversion layer CC(G) has a function of converting the colorof light emitted from the element 550G(i,j) into a different color. Forexample, the light emitted from the element 550G(i,j) passes through thefunctional layer 520 to reach the color conversion layer CC(G). Forexample, in the case where the element 550G(i,j) emits blue light, thecolor conversion layer CC(G) can convert the blue light into greenlight, for example. Note that the color conversion layer CC(G) can beformed by a photolithography method. Alternatively, the component KB isformed by a photolithography method and the color conversion layer CC(G)can be formed by an ink-jet method in a region surrounded by thecomponent KB, for example.

<<Structure Example 1 of Functional Layer 520>>

The functional layer 520 includes the insulating film 501 and the pixelcircuit 530G(i,j).

The insulating film 501 includes a region positioned between the pixelcircuit 530G(i,j) and the element 550G(i,j), and has the opening 591G.

The pixel circuit 530G(i,j) includes the transistor M21, and thetransistor M21 includes an oxide semiconductor film. The transistor M21is electrically connected to the element 550G(i,j) through the opening591G. The conductive film 512A electrically connects the transistor M21and the electrode 551(i,j), for example (see FIG. 23B). In addition, theconductive film 512B electrically connects the transistor M21 and theconductive film ANO (see FIG. 3).

Note that a light-blocking layer may be provided between the element550G(i,j) and the transistor M21. Alternatively, a light-blockingmaterial can be used for the conductive film 524. With thelight-blocking layer, the transistor M21 can be prevented from beingirradiated with light emitted from the element 550G(i,j).

Note that this embodiment can be combined with any of the otherembodiments in this specification as appropriate.

Embodiment 2

In this embodiment, structures of a functional panel of one embodimentof the present invention will be described with reference to FIG. 16,FIGS. 17A to 17C, FIGS. 18A to 18C, FIG. 19, and FIG. 20.

FIG. 16 is a block diagram illustrating the functional panel of oneembodiment of the present invention.

FIG. 17A illustrates a structure of the functional panel of oneembodiment of the present invention, and illustrates a cross-section ofthe pixel set 703(i,j) and cross sections along the cutting lines X1-X2,X3-X4, and X9-X10 in FIG. 16. FIG. 17B illustrates a structure of thefunctional panel of one embodiment of the present invention, which isdifferent from that in FIG. 17A. FIG. 17C illustrates a structure of thefunctional panel of one embodiment of the present invention, which isdifferent from those in FIGS. 17A and 17B.

FIG. 18A illustrates a structure of the functional panel of oneembodiment of the present invention and is a cross-sectional view of thepixel 702G(i,j) illustrated in FIG. 17B. FIG. 18B is a cross-sectionalview illustrating part of FIG. 18A, and FIG. 18C is a cross-sectionalview illustrating another part of FIG. 18A.

FIG. 19 is a block diagram of the functional panel of one embodiment ofthe present invention.

FIG. 20 illustrates a structure of the functional panel of oneembodiment of the present invention, and illustrates a cross-section ofthe pixel set 703(i,j) and cross sections along the cutting lines X1-X2,X3-X4, and X9-X10 in FIG. 19.

<Structure Example 1 of Functional Panel 700>

The functional panel 700 described in this embodiment includes afunctional layer 520B (see FIG. 17A and FIG. 18A).

<<Structure Example 1 of Functional Layer 520B>>

The functional layer 520B includes a contact 519 gb(j), the drivercircuit SD, and an insulating film 521C (see FIG. 18A). The contact 519gb(j) is electrically connected to the driver circuit SD.

The functional layer 520B includes an insulating film 521D. Theinsulating film 521D includes a region positioned between the drivercircuit SD and the insulating film 521C. As the insulating film 521D, afilm containing silicon and nitrogen can be used, for example. Thus,diffusion of impurities into the driver circuit SD can be inhibited.Note that the impurities might cause a malfunction.

The driver circuit SD includes a transistor MD2, and the transistor MD2includes a semiconductor containing a Group 14 element. As thetransistor MD2, a transistor formed using a single crystal siliconsubstrate can be used, for example.

The transistor MD2 includes a semiconductor film 108, a conductive film104, a conductive film 112A, and a conductive film 112B (see FIG. 18C).

The semiconductor film 108 includes a region 108A electrically connectedto the conductive film 112A and a region 108B electrically connected tothe conductive film 112B. The semiconductor film 108 includes a region108C between the region 108A and the region 108B.

The conductive film 104 includes a region overlapping with the region108C and has a function of a gate electrode.

An insulating film 106 includes a region positioned between thesemiconductor film 108 and the conductive film 104. The insulating film106 has a function of a gate insulating film.

The conductive film 112A has one of a function of a source electrode anda function of a drain electrode, and the conductive film 112B has theother.

<<Structure Example 1 of Functional Layer 520>>

The functional layer 520 includes an insulating film 521B and a contact519 ga(j) (see FIG. 18A).

The insulating film 521B includes a region positioned between theinsulating film 521C and the insulating film 521. The insulating film521B includes a region bonded to the insulating film 521C.

An insulating film containing silicon and oxygen can be used as theinsulating film 521B and the insulating film 521C, for example. Thus,the insulating film 521B and the insulating film 521C can be bonded toeach other by a surface activated bonding method, for example.Alternatively, the functional layer 520 and the functional layer 520Bcan be attached to each other.

The contact 519 ga(j) is electrically connected to the contact 519 gb(j)and the pixel circuit 530G(i,j).

For example, metal can be used for the contacts 519 ga(j) and 519 gb(j).Specifically, copper, gold, or the like can be used for the contacts 519ga(j) and 519 gb(j).

Thus, the contacts 519 ga(j) and 519 gb(j) can be electrically connectedto each other by a surface activated bonding method, for example. Theconductive film S1 g(j) can be electrically connected to the drivercircuit SD. A pixel signal can be supplied using the driver circuit SD.A transistor using single crystal silicon as a semiconductor can be usedfor the driver circuit SD, for example. The driver circuit SD can bepositioned to overlap with the pixel 702G(i,j), for example. The outersize of the functional panel can be reduced. The number of componentscan be reduced. As a result, a novel functional panel that is highlyconvenient, useful, or reliable can be provided.

<Structure Example 2 of Functional Panel 700>

Another structure of the functional panel of one embodiment of thepresent invention will be described with reference to FIG. 17B. Notethat the structure example 2 of the functional panel is different fromthe structure of the functional panel described with reference to FIG.17A in that the function layer 520B includes the driver circuit GD andthe terminal 519B. Here, the differences will be described in detailbelow, and the above description is referred to for similar portions.

For example, a transistor including a semiconductor containing a Group14 element can be used in the driver circuit GD. Specifically, atransistor containing single crystal silicon can be used in the drivercircuit GD. Thus, the driver circuit GD can be downsized. Alternatively,the outer size of the functional panel can be reduced.

<Structure Example 3 of Functional Panel 700>

Another structure of the functional panel of one embodiment of thepresent invention will be described with reference to FIG. 17C. Notethat the structure example 3 of the functional panel is different fromthe structure of the functional panel described with reference to FIG.17A in that the functional layer 520B includes the driver circuit GD,and in the position of the terminal 519B.

<Structure Example 4 of Functional Panel 700>

Another structure of the functional panel of one embodiment of thepresent invention will be described with reference to FIG. 19 and FIG.20.

Note that the structure example 4 of the functional panel is differentfrom the structure of the functional panel described with reference toFIG. 17A in that the functional layer 520 includes a driver circuit DX,the functional layer 520B includes a driver circuit DY, and the element550B(i,j) is passive-driven.

Note that this embodiment can be combined with any of the otherembodiments in this specification as appropriate.

Embodiment 3

In this embodiment, a structure of the functional panel of oneembodiment of the present invention will be described with reference toFIGS. 5A and 5B.

<Structure Example 1 of Functional Panel 700>

The functional panel 700 includes the pixel set 703(i,j), and the pixelset 703(i,j) includes the pixel 702G(i,j) and the pixel 702B(i,j) (seeFIG. 1).

<<Structure Example 1 of Pixel 702B(i,j)>>

The pixel 702B(i,j) has a function of performing display using lightemitted from the element 550B(i,j), and the element 550B(i,j) has afunction of emitting light of the same color as the light emitted fromthe element 550G(i,j). For example, the element 550B(i,j) and theelement 550G(i,j) have a function of emitting blue light.

<<Structure Example 2 of Pixel 702G(i,j)>>

The pixel 702G(i,j) includes the color conversion layer CC(G). The colorconversion layer CC(G) has a function of converting the color of lightemitted from the element 550G(i,j) into a different color.

Thus, the element 550B(i,j) can be formed in the same step as theelement 550G(i,j). Alternatively, the pixel 702G(i,j) can display acolor different from that of the pixel 702B(i,j). As a result, a novelfunctional panel that is highly convenient, useful, or reliable can beprovided.

<<Structure Example 1 of Element 550G(i,j)>>

The element 550G(i,j) includes the electrode 551G(i,j), the electrode552, and the layer 553 containing a light-emitting material (see FIG.5A). The layer 553 containing a light-emitting material includes aregion positioned between the electrode 551G(i,j) and the electrode 552.

For example, a mini-LED can be used as the element 550(i,j).Specifically, a mini-LED whose light-emitting region has an area of 1mm² or less, preferably 50000 m² or less, further preferably 30000 μm²or less, still further preferably 10000 μm² or less and 200 μm² or morecan be used as the element 550G(i,j).

Alternatively, a micro LED can be used as the element 550G(i,j).Specifically, a micro LED whose light-emitting region has an area ofless than 200 μm², preferably 60 μm² or less, further preferably 15 μm²or less, still further preferably 5 μm² or less and 3 μm² or more can beused as the element 550G(i,j).

[Structure Example 1 of Layer 553 Containing Light-Emitting Material]

The layer 553 containing a light-emitting material includes the p-typeclad layer 553P, the n-type clad layer 553N, and the light-emittinglayer 553EM, for example. The light-emitting layer 553EM includes aregion positioned between the p-type clad layer 553P and the n-type cladlayer 553N. This allows carrier recombination in the light-emittinglayer 553EM, resulting in light emission.

For example, a layered material for emitting blue light, green light, orred light can be used for the pixel. Specifically, a compound of galliumand phosphorus, a compound of gallium and arsenic, a compound ofgallium, aluminum, and arsenic, a compound of aluminum, gallium, indium,and phosphorus, a compound of indium and gallium nitride, or the likecan be used for the pixel.

In particular, an element emitting blue light can be used as the element550G(i,j) and the element 550B(i,j). Thus, the element 550G(i,j) and theelement 550B(i,j) can be formed in the same step.

Alternatively, an element emitting ultraviolet rays can be used as theelement 550G(i,j) and the element 550B(i,j). A color conversion layercan be provided to overlap with the element 550B(i,j) to convert theultraviolet rays into blue light.

<<Color Conversion Layer>>

The color conversion layer includes a region positioned between the base770 and the element 550G(i,j).

For example, a material emitting light with a wavelength longer thanthat of incident light can be used for the color conversion layer. Forexample, a material that absorbs blue light or ultraviolet rays,converts it into green light, and emits green light; a material thatabsorbs blue light or ultraviolet rays, converts it into red light, andemits red light; or a material that absorbs ultraviolet rays, convertsit into blue light, and emits blue light can be used for the colorconversion layer. For example, a phosphor can be used for the colorconversion layer. Specifically, quantum dots with a diameter of severalnanometers can be used for the color conversion layer. Thus, light witha narrow spectral half-width can be emitted. Alternatively, light withhigh saturation can be emitted.

<Structure Example 2 of Functional Panel 700>

The functional panel 700 includes a functional film 770P and the like(see FIG. 5A).

<<Functional Film 770P and the Like>>

The functional film 770P includes a region overlapping with the element550G(i,j).

For example, an anti-reflection film, a polarizing film, a retardationfilm, a light diffusion film, a condensing film, or the like can be usedas the functional film 770P.

For example, an anti-reflection film with a thickness of 1 μm or lesscan be used as the functional film 770P. Specifically, a stacked-layerfilm in which three or more, preferably five or more, further preferably15 or more dielectrics are stacked can be used as the functional film770P. This allows the reflectivity to be as low as 0.5% or less,preferably 0.08% or less.

For example, a circularly polarizing film can be used as the functionalfilm 770P.

Furthermore, an antistatic film preventing the attachment of a foreignsubstance, a water repellent film preventing stains, an oil repellentfilm preventing stains, an anti-reflection film, an anti-glare(non-glare) film, a hard coat film inhibiting a scratch in use, aself-healing film that self-heals from scratches, or the like can beused as the functional film 770P.

Note that this embodiment can be combined with any of the otherembodiments in this specification as appropriate.

Embodiment 4

In this embodiment, a structure of the functional panel of oneembodiment of the present invention will be described with reference toFIG. 7.

FIG. 7 is a block diagram illustrating a structure of the functionalpanel of one embodiment of the present invention.

<Structure Example 1 of Functional Panel 700>

The functional panel 700 described in this embodiment includes a region231 (see FIG. 7).

<<Structure Example 1 of Region 231>>

The region 231 includes a group of pixel sets 703(i,1) to 703(i,n) andanother group of pixel sets 703(1,j) to 703(m,j). The region 231includes the conductive film G1(i) and the conductive film S1 g(j).

The group of pixel sets 703(i,1) to 703(i,n) is arranged in the rowdirection (the direction indicated by an arrow R1 in FIG. 7) andincludes the pixel set 703(i,j).

Furthermore, the group of pixel sets 703(i,1) to 703(i,n) iselectrically connected to the conductive film G1(i). Furthermore, thegroup of pixel sets 703(i,1) to 703(i,n) is electrically connected tothe conductive film G2(i).

The another group of pixel sets 703(1,j) to 703(m,j) is arranged in thecolumn direction intersecting the row direction (the direction indicatedby an arrow C1 in FIG. 7) and includes the pixel set 703(i,j).

The another group of pixel sets 703(1,j) to 703(m,j) is electricallyconnected to the conductive film S1 g(j). The another group of pixelsets 703(1,j) to 703(m,j) is electrically connected to the conductivefilm S2 g(j).

Thus, image data can be supplied to a plurality of pixels.Alternatively, imaging data can be obtained from a plurality of pixels.As a result, a novel functional panel that is highly convenient, useful,or reliable can be provided.

<<Structure Example 2 of Region 231>>

The region 231 includes 600 or more pixel sets per inch, for example.Note that the plurality of pixel sets include the pixel set 703(i,j).The region 231 preferably includes 1000 or more pixel sets, furtherpreferably 3000 or more pixel sets, still further preferably 6000 ormore pixel sets per inch. This can reduce the screen-door effect.

<<Structure Example 3 of Region 231>>

The region 231 includes a plurality of pixel sets in a matrix. Forexample, the region 231 includes 7600 or more pixel sets in the rowdirection and 4300 or more pixel sets in the column direction.Specifically, the region 231 includes 7680 pixel sets in the rowdirection and 4320 pixel sets in the column direction.

Such a structure makes it possible to display a high-definition image.As a result, a novel functional panel that is highly convenient orreliable is provided.

Note that this embodiment can be combined with any of the otherembodiments in this specification as appropriate.

Embodiment 5

In this embodiment, a structure of a display device of one embodiment ofthe present invention will be described with reference to FIGS. 8A to8D.

FIG. 8A is a block diagram of a display device of one embodiment of thepresent invention, and FIGS. 8B to 8D are perspective views eachillustrating the appearance of a display device of one embodiment of thepresent invention.

<Structure Example of Display Device>

The display device described in this embodiment includes a control unit238 and the functional panel 700 (see FIG. 8A).

<<Structure example 1 of control unit 238>>

The control unit 238 is supplied with image data VI and control data CI.For example, a clock signal, a timing signal, or the like can be used asthe control data CI.

The control unit 238 generates data on the basis of the image data VIand generates a control signal on the basis of the control data CI.Moreover, the control unit 238 supplies the data and the control signal.

For example, the data includes gray levels of 8 bits or more, preferably12 bits or more. A clock signal, a start pulse, or the like of a shiftregister used in a driver circuit, for example, can be used as thecontrol signal.

<<Structure Example 2 of Control Unit 238>>

For example, a decompression circuit 234 and an image processing circuit235 can be used in the control unit 238.

<<Decompression Circuit 234>>

The decompression circuit 234 has a function of decompressing the imagedata VI that is supplied in a compressed state. The decompressioncircuit 234 includes a memory unit. The memory unit has a function ofstoring decompressed image data, for example.

<<Image Processing Circuit 235>>

The image processing circuit 235 includes a memory region, for example.The memory region has a function of storing data contained in the imagedata VI, for example.

The image processing circuit 235 has a function of generating data bycorrecting the image data VI on the basis of a predeterminedcharacteristics curve and a function of supplying the data, for example.

<<Structure Example 1 of Functional Panel 700>>

The functional panel 700 is supplied with the data and the controlsignal. For example, the functional panel 700 described in any one ofEmbodiments 1 to 4 can be used.

<<Structure Example 3 of Pixel Set 703(i,j)>>

The pixel set 703(i,j) performs display on the basis of the data.

Thus, the image data VI can be displayed using the element 550G(i,j).Consequently, a novel display device that is highly convenient, useful,or reliable can be provided. For example, an information terminal (seeFIG. 8B), a video display system (see FIG. 8C), or a computer (see FIG.8D) can be provided.

<<Structure Example 2 of Functional Panel 700>>

For example, the functional panel 700 includes driver circuits andcontrol circuits.

<<Driver Circuit>>

The driver circuit operates on the basis of the control signal. The useof the control signal enables a plurality of driver circuits to operatein synchronization with each other (see FIG. 8A).

For example, the driver circuit GD can be used in the functional panel700. The driver circuit GD is supplied with the control signal and has afunction of supplying a first selection signal.

For example, a driver circuit SD can be used in the functional panel700. The driver circuit SD is supplied with the control signal and thedata, and can supply an image signal.

<<Control Circuit>>

A control circuit has a function of generating and supplying the controlsignal. For example, a clock signal, a timing signal, or the like can beused as the control signal.

Specifically, a control circuit formed over a rigid substrate can beused in the functional panel. Alternatively, a control circuit formedover a rigid substrate can be electrically connected to the control unit238 with the use of a flexible printed circuit.

<<Control Circuit 233>>

A timing controller can be used as the control circuit, for example.

Note that this embodiment can be combined with any of the otherembodiments in this specification as appropriate.

Embodiment 6

In this embodiment, a structure of an input/output device of oneembodiment of the present invention will be described with reference toFIG. 9.

FIG. 9 is a block diagram illustrating a structure of an input/outputdevice of one embodiment of the present invention.

<Structure Example 1 of Input/Output Device>

The input/output device described in this embodiment includes an inputunit 240 and a display unit 230 (see FIG. 9).

<<Structure Example 1 of Display Unit 230>>

The display unit 230 includes the functional panel 700. For example, thefunctional panel 700 described in any one of Embodiments 1 to 4 can beused as the display unit 230. Note that the panel including the inputunit 240 and the display unit 230 can be referred to as a functionalpanel 700TP.

<<Structure Example 1 of Input Unit 240>>

The input unit 240 includes a sensing region 241. The input unit 240senses an object approaching the sensing region 241.

The sensing region 241 includes a region overlapping with the pixel set703(i,j).

Accordingly, an object that approaches the region overlapping with thedisplay unit can be sensed while image data is displayed using thedisplay unit 230. Alternatively, a finger or the like that approachesthe display unit 230 can be used as a pointer to input positional data.Alternatively, positional data can be associated with image datadisplayed on the display unit 230. Consequently, a novel input/outputdevice that is highly convenient, useful, or reliable can be provided.

<<Structure Example 1 of Sensing Region 241>>

The sensing region 241 can include one or more sensors, for example.

The sensing region 241 includes a group of sensors 802(g,1) to 802(g,q)and another group of sensors 802(1,h) to 802(p,h). Note that g is aninteger greater than or equal to 1 and less than or equal top, h is aninteger greater than or equal to 1 and less than or equal to q, and eachof p and q is an integer greater than or equal to 1.

The group of sensors 802(g,1) to 802(g,q) includes the sensor 802(g,h),is arranged in the row direction (the direction indicated by an arrow R2in FIG. 9), and is electrically connected to a wiring CL(g). Note thatthe direction indicated by the arrow R2 may be the same as or differentfrom the direction indicated by the arrow R1.

The another group of sensors 802(1,h) to 802(p,h) includes the sensor802(g,h), is arranged in the column direction intersecting the rowdirection (the direction indicated by the arrow C2 in FIG. 9), and iselectrically connected to a wiring ML(h).

<<Sensor>>

The sensor has a function of sensing an approaching pointer. Forexample, a finger or a stylus pen can be used as the pointer. Forexample, a piece of metal or a coil can be used as the stylus pen.

Specifically, a capacitive proximity sensor, an electromagneticinductive proximity sensor, an optical proximity sensor, a resistiveproximity sensor, or the like can be used as the sensor.

Alternatively, a plurality of kinds of sensors can be used incombination. For example, a sensor that senses a finger and a sensorthat senses a stylus pen can be used in combination.

Accordingly, the kind of a pointer can be identified. Alternatively, adifferent instruction can be associated with sensing data on the basisof the kind of the identified pointer. Specifically, when a finger isidentified as being used as the pointer, sensing data can be associatedwith a gesture. Meanwhile, when a stylus pen is identified as being usedas the pointer, sensing data can be associated with drawing processing.

Specifically, a finger can be sensed using a capacitive,pressure-sensitive, or optical proximity sensor. Alternatively, a styluspen can be sensed using an electromagnetic inductive or opticalproximity sensor.

<<Structure Example 2 of Input Unit 240>>

The input unit 240 can include an oscillator circuit OSC and a sensorcircuit DC (see FIG. 9).

The oscillator circuit OSC supplies a search signal to the sensor802(g,h). For example, a rectangular wave, a sawtooth wave, a triangularwave, or a sine wave can be used as the search signal.

The sensor 802(g,h) generates and supplies a sensing signal that changesin accordance with the search signal and the distance to a pointerapproaching the sensor 802(g,h).

The sensor circuit DC supplies input data in accordance with the sensingsignal.

Accordingly, the distance from an approaching pointer to the sensingregion 241 can be sensed. Alternatively, the position in the sensingregion 241 where the pointer comes the closest can be sensed.

Note that this embodiment can be combined with any of the otherembodiments in this specification as appropriate.

Embodiment 7

In this embodiment, a structure of a data processing device of oneembodiment of the present invention will be described with reference toFIGS. 10A to 10C, FIGS. 11A and 11B, and FIGS. 12A to 12C.

FIG. 10A is a block diagram illustrating a structure of a dataprocessing device of one embodiment of the present invention. FIGS. 10Band 10C are projection views each illustrating an example of theappearance of a data processing device.

FIGS. 11A and 11B are flow charts showing a program of one embodiment ofthe present invention. FIG. 11A is a flow chart showing main processingof the program of one embodiment of the present invention, and FIG. 11Bis a flow chart showing interrupt processing.

FIGS. 12A to 12C illustrate a program of one embodiment of the presentinvention. FIG. 12A is a flow chart showing interrupt processing of theprogram of one embodiment of the present invention. FIG. 12B is aschematic view illustrating handling of a data processing device, andFIG. 12C is a timing chart showing operation of the data processingdevice of one embodiment of the present invention.

<Structure Example 1 of Data Processing Device>

The data processing device described in this embodiment includes anarithmetic device 210 and an input/output device 220 (see FIG. 10A). Theinput/output device 220 is electrically connected to the arithmeticdevice 210. The data processing device 200 can include a housing (seeFIG. 10B and FIG. 10C).

<<Structure Example 1 of Arithmetic Device 210>>

The arithmetic device 210 is supplied with input data II or sensing dataDS. The arithmetic device 210 generates the control data CI and theimage data VI on the basis of the input data II or the sensing data DS,and supplies the control data CI and the image data VI.

The arithmetic device 210 includes an arithmetic unit 211 and a memoryunit 212. The arithmetic device 210 also includes a transmission path214 and an input/output interface 215.

The transmission path 214 is electrically connected to the arithmeticunit 211, the memory unit 212, and the input/output interface 215.

<<Arithmetic Unit 211>>

The arithmetic unit 211 has a function of executing a program, forexample.

<<Memory Unit 212>>

The memory unit 212 has a function of, for example, storing a programexecuted by the arithmetic unit 211, initial data, setting data, animage, or the like.

Specifically, a hard disk, a flash memory, a memory using a transistorincluding an oxide semiconductor, or the like can be used.

<<Input/Output Interface 215 and Transmission Path 214>>

The input/output interface 215 includes a terminal or a wiring and has afunction of supplying data and receiving data. For example, theinput/output interface 215 can be electrically connected to thetransmission path 214. Moreover, the input/output interface 215 can beelectrically connected to the input/output device 220.

The transmission path 214 includes a wiring and has a function ofsupplying data and receiving data. For example, the transmission path214 can be electrically connected to the input/output interface 215. Inaddition, the transmission path 214 can be electrically connected to thearithmetic unit 211, the memory unit 212, or the input/output interface215.

<<Structure Example of Input/Output Device 220>>

The input/output device 220 supplies the input data II and the sensingdata DS. The input/output device 220 is supplied with the control dataCI and the image data VI (see FIG. 10A).

For example, a keyboard scan code, positional data, data on buttonhandling, sound data, or image data can be used as the input data II.For example, data on illuminance, attitude, acceleration, direction,pressure, temperature, or humidity of the environment where the dataprocessing device 200 is used, for example, can be used as the sensingdata DS.

For example, a signal for controlling the luminance, a signal forcontrolling the color saturation, or a signal for controlling the hue todisplay the image data VI can be used as the control data CI.Alternatively, a signal for changing part of display based on the imagedata VI can be used as the control data CI.

The input/output device 220 includes the display unit 230, the inputunit 240, and a sensor unit 250. For example, the input/output devicedescribed in Embodiment 6 can be used as the input/output device 220.The input/output device 220 can include a communication unit 290.

<<Structure Example of Display Unit 230>>

The display unit 230 displays the image data VI on the basis of thecontrol data CI. The display device described in Embodiment 5 can beused for the display unit 230, for example.

<<Structure Example of Input Unit 240>>

The input unit 240 generates the input data II. The input unit 240 has afunction of supplying positional data, for example.

For example, a human interface or the like can be used as the input unit240 (see FIG. 10A). Specifically, a keyboard, a mouse, a touch sensor, amicrophone, a camera, or the like can be used as the input unit 240.

A touch sensor having a region overlapping with the display unit 230 canbe used. Note that an input/output device that includes the display unit230 and a touch sensor having a region overlapping with the display unit230 can be referred to as a touch panel or a touch screen.

For example, a user can make various gestures (e.g., tap, drag, swipe,and pinch in) using a finger on the touch panel as a pointer.

The arithmetic device 210, for example, analyzes data on the position,track, or the like of the finger on the touch panel and determines thata predetermined gesture is supplied when the analysis results meetpredetermined conditions. Therefore, the user can supply a certainoperating instruction associated with a predetermined gesture by usingthe gesture.

For example, the user can supply a scrolling instruction for changingthe position where image data is displayed, by using a gesture oftouching and moving a finger on the touch panel.

The user can supply a dragging instruction for pulling out anddisplaying a navigation panel NP at an edge portion of the region 231,by using a gesture of moving a finger touching the edge portion of theregion 231 (see FIG. 10C). Moreover, the user can supply a leafingthrough instruction for displaying index images IND, some parts of otherpages, or thumbnail images TN of other pages in a predetermined order onthe navigation panel NP so that the user can flip through these images,by using a gesture of moving the position where a finger presses hard orby using the pressure of pressing the finger. Consequently, the user canturn the pages of an e-book reader like flipping through the pages of apaper book. Moreover, the user can search a given page with the aid ofthe thumbnail images TN or the index images IND.

<<Structure Example of Sensor Unit 250>>

The sensor unit 250 generates the sensing data DS. The sensor unit 250has a function of sensing the illuminance of the environment where thedata processing device 200 is used and a function of supplyingilluminance data, for example.

The sensor unit 250 has a function of sensing the ambient conditions andsupplying the sensing data. Specifically, the sensor unit 250 can supplydata on illuminance, attitude, acceleration, direction, pressure,temperature, humidity, or the like.

For example, a photosensor, an attitude sensor, an acceleration sensor,a direction sensor, a global positioning system (GPS) signal receivingcircuit, a pressure-sensitive switch, a pressure sensor, a temperaturesensor, a humidity sensor, or a camera can be used as the sensor unit250.

<<Communication Unit 290>>

The communication unit 290 has a function of supplying data to a networkand acquiring data from a network.

<<Housing>>

The housing has a function of housing the input/output device 220 or thearithmetic device 210. Alternatively, the housing has a function ofsupporting the display unit 230 or the arithmetic device 210.

Accordingly, the control data CI can be generated on the basis of theinput data II or the sensing data DS. Alternatively, the image data VIcan be displayed on the basis of the input data II or the sensing dataDS. Alternatively, the data processing device is capable of operatingwith knowledge of the intensity of light that the housing of the dataprocessing device receives in the environment where the data processingdevice is used. Alternatively, the user of the data processing devicecan select a display method. Consequently, a novel data processingdevice that is highly convenient, useful, or reliable can be provided.

Note that in some cases, these components cannot be clearlydistinguished from each other and one component may also serve asanother component or include part of another component. For example, atouch panel in which a touch sensor overlaps with a display panel servesas an input unit as well as a display unit.

<<Structure Example 2 of Arithmetic Device 210>>

The arithmetic device 210 includes an artificial intelligence unit 213(see FIG. 10A).

The artificial intelligence unit 213 is supplied with the input data IIor the sensing data DS, and infers the control data CI on the basis ofthe input data II or the sensing data DS. Moreover, the artificialintelligence unit 213 supplies the control data CI.

In this manner, the control data CI for performing display which theuser finds suitable can be generated. Alternatively, it is possible toperform display which the user finds suitable. Alternatively, thecontrol data CI for performing display which the user finds comfortablecan be generated. Alternatively, it is possible to perform display whichthe user finds comfortable. Consequently, a novel data processing devicethat is highly convenient, useful, or reliable can be provided.

[Natural Language Processing on Input Data II]

Specifically, the artificial intelligence unit 213 can perform naturallanguage processing on the input data II and extract one feature fromthe whole input data II. For example, the artificial intelligence unit213 can infer emotion or the like in the input data II and regard theinference as a feature. The artificial intelligence unit 213 can alsoinfer the color, design, font, or the like empirically felt suitable forthe feature. The artificial intelligence unit 213 can also generate dataspecifying the color, design, or font of a letter or data specifying thecolor or design of the background, and use the generated data as thecontrol data CI.

Specifically, the artificial intelligence unit 213 can perform naturallanguage processing on the input data II and extract some words includedin the input data II. For example, the artificial intelligence unit 213can extract expressions including a grammatical error, a factual error,emotion, or the like. Moreover, the artificial intelligence unit 213 cangenerate data for displaying extracted part in the color, design, font,or the like different from those of another part, and use the generateddata as the control data CI.

[Image Processing on Input Data II]

Specifically, the artificial intelligence unit 213 can perform imageprocessing on the input data II and extract one feature from the inputdata II. For example, the artificial intelligence unit 213 can infer theage where the input data II was captured, whether the input data II wascaptured indoors or outdoors, or whether the input data II was capturedin the daytime or at night, for example, and regard the inference as afeature. The artificial intelligence unit 213 can also infer the colortone empirically felt suitable for the feature and generate the controldata CI for using the color tone for display. Specifically, dataspecifying color (e.g., full color, monochrome, or sepia) used forexpressing a gradation can be used as the control data CI.

Specifically, the artificial intelligence unit 213 can perform imageprocessing on the input data II and extract some images included in theinput data II. For example, the artificial intelligence unit 213 cangenerate the control data CI for displaying a boundary between one partand another part of the extracted image. Specifically, the artificialintelligence unit 213 can generate the control data CI for displaying arectangle surrounding part of the extracted image.

[Inference Using Sensing Data DS]

Specifically, the artificial intelligence unit 213 can make inferencewith the use of the sensing data DS. Alternatively, the artificialintelligence unit 213 can generate the control data CI on the basis ofthe inference so that the user of the data processing device 200 canfeel comfortable.

Specifically, the artificial intelligence unit 213 can generate thecontrol data CI for adjusting display brightness on the basis of theambient illuminance or the like to provide comfortable displaybrightness. The artificial intelligence unit 213 can also generate thecontrol data CI for adjusting volume on the basis of the ambient noiseor the like to provide comfortable volume.

As the control data CI, a clock signal, a timing signal, or the likethat is supplied to the control unit 238 included in the display unit230 can be used. A clock signal, a timing signal, or the like that issupplied to a control unit included in the input unit 240 can also beused as the control data CI.

<Structure Example 2 of Data Processing Device>

Another structure of the data processing device of one embodiment of thepresent invention will be described with reference to FIGS. 11A and 11B.

<<Program>>

A program of one embodiment of the present invention includes thefollowing steps (see FIG. 11A).

[First Step]

In a first step, the setting is initialized (see S1 in FIG. 11A).

For example, predetermined image data that is to be displayed onstart-up and data for determining a predetermined mode of displaying theimage data and a predetermined method of displaying the image data areacquired from the memory unit 212. Specifically, still image data ormoving image data can be used as the predetermined image data.Furthermore, a first mode or a second mode can be used as thepredetermined mode.

[Second Step]

In a second step, interrupt processing is allowed (see S2 in FIG. 11A).Note that an arithmetic device allowed to execute the interruptprocessing can perform the interrupt processing in parallel with themain processing. The arithmetic device which has returned from theinterrupt processing to the main processing can reflect the results ofthe interrupt processing in the main processing.

The arithmetic device may execute the interrupt processing when acounter has an initial value, and the counter may be set at a valueother than the initial value when the arithmetic device returns from theinterrupt processing. Thus, the interrupt processing is always ready tobe executed after the program is started up.

[Third Step]

In a third step, image data is displayed in a predetermined mode or apredetermined display method selected in the first step or the interruptprocessing (see S3 in FIG. 11A). Note that the predetermined modeidentifies a mode for displaying data, and the predetermined displaymethod identifies a method of displaying the data. For example, theimage data VI can be used as data to be displayed.

For example, one method of displaying the image data VI can beassociated with the first mode. Another method of displaying the imagedata VI can be associated with the second mode. Thus, a display methodcan be selected on the basis of the selected mode.

<<First Mode>>

Specifically, a method of supplying selection signals to a scan line ata frequency of 30 Hz or more, preferably 60 Hz or more and performingdisplay in accordance with the selection signals can be associated withthe first mode.

For example, the supply of selection signals at a frequency of 30 Hz ormore, preferably 60 Hz or more enables motion in a moving image to bedisplayed smoothly.

For example, refreshing an image at a frequency of 30 Hz or more,preferably 60 Hz or more allows the data processing device 200 that theuser is using to display an image smoothly following the user'soperation.

<<Second Mode>>

Specifically, a method of supplying selection signals to a scan line ata frequency less than 30 Hz, preferably less than 1 Hz, furtherpreferably less than once a minute and performing display in accordancewith the selection signals can be associated with the second mode.

The supply of selection signals at a frequency less than 30 Hz,preferably less than 1 Hz, further preferably less than once a minuteallows display with flickering reduced. Furthermore, power consumptioncan be reduced.

For example, when the data processing device 200 is used in a clock or awatch, the display can be refreshed once a second, once a minute, or thelike.

[Fourth Step]

In a fourth step, the program moves to a fifth step when a terminationinstruction has been supplied, whereas the program moves to the thirdstep when the termination instruction has not been supplied (see S4 inFIG. 11A).

For example, a termination instruction supplied in the interruptprocessing can be used to determine the next step.

[Fifth Step]

In the fifth step, the program terminates (see S5 in FIG. 11A).

<<Interrupt Processing>>

The interrupt processing includes sixth to eighth steps described below(see FIG. 11B).

[Sixth Step]

In the sixth step, the illuminance of the environment where the dataprocessing device 200 is used is sensed using the sensor unit 250, forexample (see S6 in FIG. 11B). Note that the color temperature orchromaticity of ambient light may be sensed instead of the illuminanceof the environment.

[Seventh Step]

In the seventh step, a display method is determined on the basis of thesensed illuminance data (see S7 in FIG. 11B). For example, a displaymethod is determined such that the brightness of display is not toobright or too dark.

In the case where the color temperature or chromaticity of the ambientlight is sensed in the sixth step, the color of display may be adjusted.

[Eighth Step]

In the eighth step, the interrupt processing terminates (see S8 in FIG.11B).

<Structure Example 3 of Data Processing Device>

Another structure of the data processing device of one embodiment of thepresent invention will be described with reference to FIGS. 12A to 12C.

FIG. 12A is a flow chart showing a program of one embodiment of thepresent invention. The interrupt processing in the flow chart in FIG.12A is different from that in FIG. 11B.

Note that the structure example 3 of the data processing device isdifferent from the interrupt processing in FIG. 11B in that theinterrupt processing includes a step of changing a mode on the basis ofa supplied predetermined event. Here, the differences will be describedin detail below, and the above description is referred to for similarportions.

<<Interrupt Processing>>

The interrupt processing includes the following sixth to eighth steps(see FIG. 12A).

[Sixth Step]

In the sixth step, the processing proceeds to the seventh step when apredetermined event has been supplied, whereas the processing proceedsto the eighth step when the predetermined event has not been supplied(see U6 in FIG. 12A). For example, whether the predetermined event issupplied in a predetermined period or not can be a branch condition.Specifically, the predetermined period can be a period longer than 0seconds and 5 seconds or less, 1 second or less, 0.5 seconds or less,preferably 0.1 seconds or less.

[Seventh Step]

In the seventh step, the mode is changed (see U7 in FIG. 12A).Specifically, the mode is changed from the first mode to the secondmode, or the mode is changed from the second mode to the first mode.

For example, a display mode of part of a region in the display unit 230can be changed. Specifically, it is possible to change a display mode ofa region where one driver circuit in the display unit 230 including adriver circuit GDA, a driver circuit GDB, and a driver circuit GDCsupplies a selection signal (see FIG. 12B).

For example, the display mode of the region where a selection signal issupplied from the driver circuit GDB can be changed when a predeterminedevent is supplied to the input unit 240 in a region overlapping with theregion where a selection signal is supplied from the driver circuit GDB(see FIGS. 12B and 12C). Specifically, the frequency of the selectionsignal supplied from the driver circuit GDB can be changed in accordancewith a “tap” event supplied to a touch panel with a finger or the like.

A signal GCLK is a clock signal for controlling the operation of thedriver circuit GDB, and signals PWC1 and PWC2 are pulse width controlsignals for controlling the operation of the driver circuit GDB. Thedriver circuit GDB supplies selection signals to conductive filmsG2(m+1) to G2(2m) on the basis of the signals GCLK, PWC1, PWC2, and thelike.

Thus, for example, the driver circuit GDB can supply selection signalswithout supply of selection signals from the driver circuits GDA andGDC. Alternatively, the display of the region where selection signalsare supplied from the driver circuit GDB can be refreshed without anychange in the display of regions where selection signals are suppliedfrom the driver circuits GDA and GDC. Alternatively, power consumed bythe driver circuits can be reduced.

[Eighth Step]

In the eighth step, the interrupt processing terminates (see U8 in FIG.12A). Note that the interrupt processing may be repeatedly executed in aperiod during which the main processing is executed.

<<Predetermined Event>>

For example, the following events can be used: events supplied using apointing device such as a mouse (e.g., click and drag) and eventssupplied to a touch panel with a finger or the like used as a pointer(e.g., tap, drag, and swipe).

For example, the position of a slide bar pointed by a pointer, the swipespeed, and the drag speed can be used as parameters assigned to aninstruction associated with a predetermined event.

For example, data sensed by the sensor unit 250 is compared to apredetermined threshold value, and the compared results can be used forthe event.

Specifically, a pressure sensor or the like in contact with a button orthe like that can be pushed in a housing can be used as the sensor unit250.

<<Instruction Associated with Predetermined Event>>

For example, a termination instruction can be associated with apredetermined event.

For example, a page-turning instruction for switching displayed imagedata from one to another can be associated with a predetermined event.Note that a parameter determining the page-turning speed or the likewhen the page-turning instruction is executed can be supplied using thepredetermined event.

For example, a scroll instruction for moving the position of displayedpart of image data and displaying another part continuing from that partcan be associated with a predetermined event. Note that a parameterdetermining the moving speed of the display, for example, when thescroll instruction is executed can be supplied using the predeterminedevent.

For example, an instruction for setting the display method or aninstruction for generating image data can be associated with apredetermined event. Note that a parameter determining the brightness ofa generated image can be associated with the predetermined event. Aparameter determining the brightness of a generated image may bedetermined on the basis of ambient brightness sensed by the sensor unit250.

For example, an instruction for acquiring data distributed via a pushservice using the communication unit 290 can be associated with apredetermined event.

Note that positional data sensed by the sensor unit 250 may be used todetermine the presence or absence of a qualification for acquiring data.Specifically, the user may be considered to have a qualification foracquiring data when the user is in a predetermined class room, school,conference room, office, building, or the like. Accordingly, forexample, the data processing device 200 that receives educationalmaterials distributed in a classroom of a school or a university can beused as a schoolbook or the like (see FIG. 10C). Alternatively,materials distributed in a company's conference room, for example, canbe received and used for a conference material.

Note that this embodiment can be combined with any of the otherembodiments in this specification as appropriate.

Embodiment 8

In this embodiment, a structure of a data processing device of oneembodiment of the present invention will be described with reference toFIGS. 13A to 13E, FIGS. 14A to 14E, and FIGS. 15A and 15B.

FIGS. 13A to 13E, FIGS. 14A to 14E, and FIGS. 15A and 15B illustratestructures of a data processing device of one embodiment of the presentinvention.

FIG. 13A is a block diagram of a data processing device, and FIGS. 13Bto 13E are perspective views each illustrating a structure of the dataprocessing device. FIGS. 14A to 14E are perspective views eachillustrating a structure of the data processing device. FIGS. 15A and15B are perspective views each illustrating a structure of the dataprocessing device.

<Data Processing Device>

A data processing device 5200B described in this embodiment includes anarithmetic device 5210 and an input/output device 5220 (see FIG. 13A).

The arithmetic device 5210 has a function of receiving handling data anda function of supplying image data on the basis of the handling data.

The input/output device 5220 includes a display unit 5230, an input unit5240, a sensor unit 5250, and a communication unit 5290, and has afunction of supplying handling data and a function of receiving imagedata. The input/output device 5220 also has a function of supplyingsensing data, a function of supplying communication data, and a functionof receiving communication data.

The input unit 5240 has a function of supplying handling data. Forexample, the input unit 5240 supplies handling data on the basis ofhandling by a user of the data processing device 5200B.

Specifically, a keyboard, a hardware button, a pointing device, a touchsensor, an illuminance sensor, an imaging device, an audio input device,an eye-gaze input device, an attitude sensing device, or the like can beused as the input unit 5240.

The display unit 5230 includes a display panel and has a function ofdisplaying image data. For example, the display panel described in anyof Embodiments 1 to 4 can be used in the display unit 5230.

The sensor unit 5250 has a function of supplying sensing data. Forexample, the sensor unit 5250 has a function of sensing a surroundingenvironment where the data processing device is used and supplyingsensing data.

Specifically, an illuminance sensor, an imaging device, an attitudesensing device, a pressure sensor, a human motion sensor, or the likecan be used as the sensor unit 5250.

The communication unit 5290 has a function of receiving and supplyingcommunication data. For example, the communication unit 5290 has afunction of being connected to another electronic device or acommunication network by wireless communication or wired communication.Specifically, the communication unit 5290 has a function of wirelesslocal area network communication, telephone communication, or near fieldcommunication, for example.

<<Structure Example 1 of Data Processing Device>>

For example, the display unit 5230 can have an outer shape along acylindrical column (see FIG. 13B). The data processing device has afunction of changing its display method in accordance with theilluminance of a usage environment. In addition, the data processingdevice has a function of changing the displayed content when sensing theexistence of a person. This allows the data processing device to beprovided on a column of a building, for example. The data processingdevice can display advertising, guidance, or the like. The dataprocessing device can be used for digital signage or the like.

<<Structure Example 2 of Data Processing Device>>

For example, the data processing device has a function of generatingimage data on the basis of the path of a pointer used by a user (seeFIG. 13C). Specifically, a display panel with a diagonal size of 20inches or longer, preferably 40 inches or longer, further preferably 55inches or longer can be used. Alternatively, a plurality of displaypanels can be arranged and used as one display region. Alternatively, aplurality of display panels can be arranged and used as a multiscreen.Thus, the data processing device can be used for an electronicblackboard, an electronic bulletin board, or digital signage, forexample.

<<Structure Example 3 of Data Processing Device>>

The data processing device can receive data from another device, and thedata can be displayed on the display unit 5230 (see FIG. 13D). Moreover,several options can be displayed. The user can choose some from theoptions and send a reply to the data transmitter. As another example,the data processing device has a function of changing its display methodin accordance with the illuminance of a usage environment. Thus, it ispossible to obtain a smartwatch with reduced power consumption, forexample. As another example, it is possible to obtain a smartwatch whichcan display an image such that the smartwatch can be suitably used in anenvironment under strong external light, e.g., outdoors in fine weather.

<<Structure Example 4 of Data Processing Device>>

For example, the display unit 5230 has a surface gently curved along aside surface of a housing (see FIG. 13E). The display unit 5230 includesa display panel that is capable of displaying an image on the frontsurface, the side surfaces, the top surface, and the rear surface, forexample. Thus, it is possible to obtain a mobile phone that can displayimage data on not only its front surface but also its side surfaces, topsurface, and rear surface, for example.

<<Structure Example 5 of Data Processing Device>>

For example, the data processing device can receive data via theInternet and display the data on the display unit 5230 (see FIG. 14A).The user can check a created message on the display unit 5230 or sendthe created message to another device. As another example, the dataprocessing device has a function of changing its display method inaccordance with the illuminance of a usage environment. Thus, it ispossible to obtain a smartphone with reduced power consumption.Alternatively, for example, it is possible to obtain a smartphone whichcan display an image such that the smartphone can be suitably used in anenvironment under strong external light, e.g., outdoors in fine weather.

<<Structure Example 6 of Data Processing Device>>

A remote controller can be used as the input unit 5240 (see FIG. 14B).For example, the data processing device can receive data from abroadcast station or via the Internet and display the data on thedisplay unit 5230. Alternatively, the data processing device can take animage of the user with the sensor unit 5250 and transmit the image ofthe user. The data processing device can acquire a viewing history ofthe user and provide it to a cloud service. The data processing devicecan acquire recommendation data from a cloud service and display thedata on the display unit 5230. A program or a moving image can bedisplayed on the basis of the recommendation data. As another example,the data processing device has a function of changing its display methodin accordance with the illuminance of a usage environment. Accordingly,for example, it is possible to obtain a television system which candisplay an image such that the television system can be suitably usedeven when irradiated with strong external light that enters the roomfrom the outside in fine weather.

<<Structure Example 7 of Data Processing Device>>

For example, the data processing device can receive educationalmaterials via the Internet and display them on the display unit 5230(see FIG. 14C). The user can input an assignment with the input unit5240 and send it via the Internet. The user can obtain a correctedassignment or the evaluation from a cloud service and have it displayedon the display unit 5230. The user can select suitable educationalmaterials on the basis of the evaluation and have them displayed.

For example, the display unit 5230 can perform display using an imagesignal received from another data processing device. When the dataprocessing device is placed on a stand or the like, the display unit5230 can be used as a sub-display. Thus, for example, it is possible toobtain a tablet computer which can display an image such that the tabletcomputer is favorably used even in an environment under strong externallight, e.g., outdoors in fine weather.

<<Structure Example 8 of Data Processing Device>>

The data processing device includes, for example, a plurality of displayunits 5230 (see FIG. 14D). For example, the display unit 5230 candisplay an image that the sensor unit 5250 is capturing. A capturedimage can be displayed on the sensor unit. A captured image can bedecorated using the input unit 5240. A message can be attached to acaptured image. A captured image can be transmitted via the Internet.The data processing device has a function of changing shootingconditions in accordance with the illuminance of a usage environment.Accordingly, for example, it is possible to obtain a digital camera thatcan display a subject such that an image is favorably viewed even in anenvironment under strong external light, e.g., outdoors in fine weather.

<<Structure Example 9 of Data Processing Device>>

For example, the data processing device of this embodiment is used as amaster and another data processing device is used as a slave, wherebythe other data processing device can be controlled (see FIG. 14E). Asanother example, part of image data can be displayed on the display unit5230 and another part of the image data can be displayed on a displayunit of another data processing device. In addition, image signals canbe supplied. Alternatively, with the communication unit 5290, data to bewritten can be obtained from an input unit of another data processingdevice. Thus, a large display region can be utilized by using a portablepersonal computer, for example.

<<Structure Example 10 of Data Processing Device>>

The data processing device includes, for example, the sensor unit 5250that senses an acceleration or a direction (see FIG. 15A). The sensorunit 5250 can supply data on the position of the user or the directionin which the user faces. The data processing device can generate imagedata for the right eye and image data for the left eye in accordancewith the position of the user or the direction in which the user faces.The display unit 5230 includes a display region for the right eye and adisplay region for the left eye. Thus, a virtual reality image thatgives the user a sense of immersion can be displayed on a goggles-typedata processing device, for example.

<<Structure Example 11 of Data Processing Device>>

The data processing device includes, for example, an imaging device andthe sensor unit 5250 that senses an acceleration or a direction (seeFIG. 15B). The sensor unit 5250 can supply data on the position of theuser or the direction in which the user faces. Alternatively, the dataprocessing device can generate image data in accordance with theposition of the user or the direction in which the user faces.Accordingly, the data can be shown together with a real-world scene, forexample. Alternatively, an augmented reality image can be displayed on aglasses-type data processing device.

Note that this embodiment can be combined with any of the otherembodiments in this specification as appropriate.

Embodiment 9

In this embodiment, a structure of a transistor that can be used in thefunctional panel of one embodiment of the present invention will bedescribed with reference to FIGS. 21A to 21D. For example, the structurecan be used for the transistor M21, the transistor MD, or the like ofthe functional panel of one embodiment of the present invention, whichis described in Embodiment 1.

<Structure Example of Semiconductor Device>

A structure of a semiconductor device including a transistor 300 will bedescribed with reference to FIGS. 21A to 21D. FIGS. 21A to 21D are atopview and cross-sectional views of the semiconductor device including thetransistor 300. FIG. 21A is the top view of the semiconductor device.FIGS. 21B to 21D are the cross-sectional views of the semiconductordevice. FIG. 21B is a cross-sectional view taken along dashed-dottedline A1-A2 in FIG. 21A, which corresponds to a cross-sectional view ofthe transistor 300 in the channel length direction. FIG. 21C is across-sectional view taken along dashed-dotted line A3-A4 in FIG. 21A,which corresponds to a cross-sectional view of the transistor 300 in thechannel width direction. FIG. 21D is a cross-sectional view taken alongdashed-dotted line A5-A6 in FIG. 21A. Note that for simplification, somecomponents are not illustrated in the top view in FIG. 21A.

An insulator, a conductor, an oxide, or a semiconductor described belowcan be deposited by a sputtering method, a chemical vapor deposition(CVD) method, a molecular beam epitaxy (MBE) method, a pulsed laserdeposition (PLD) method, an atomic layer deposition (ALD) method, or thelike. In this specification and the like, the term “insulator” can bereplaced with an insulating film or an insulating layer. The term“conductor” can be replaced with a conductive film or a conductivelayer. The term “oxide” can be replaced with an oxide film or an oxidelayer. The term “semiconductor” can be replaced with a semiconductorfilm or a semiconductor layer.

The semiconductor device of one embodiment of the present inventionincludes an insulator 312 over a substrate (not illustrated), aninsulator 314 over the insulator 312, the transistor 300 over theinsulator 314, an insulator 380 over the transistor 300, an insulator382 over the insulator 380, an insulator 383 over the insulator 382, andan insulator 385 over the insulator 383. The insulators 312, 314, 380,382, 383, and 385 each function as an interlayer insulating film. Thesemiconductor device also includes a conductor 340 (a conductor 340 aand a conductor 340 b) that is electrically connected to the transistor300 and functions as a plug. Note that an insulator 341 (an insulator341 a and an insulator 341 b) is provided in contact with a side surfaceof the conductor 340 functioning as a plug. A conductor 346 (a conductor346 a and a conductor 346 b) electrically connected to the conductor 340and functioning as a wiring is provided over the insulator 385 and theconductor 340.

The insulator 341 a is provided in contact with an inner wall of anopening formed in the insulators 380, 382, 383, and 385, a firstconductor of the conductor 340 a is provided in contact with the sidesurface of the insulator 341 a, and a second conductor of the conductor340 a is provided inside the first conductor. The insulator 341 b isprovided in contact with an inner wall of an opening formed in theinsulators 380, 382, 383, and 385, a first conductor of the conductor340 b is provided in contact with the side surface of the insulator 341b, and a second conductor of the conductor 340 b is provided inside thefirst conductor. A top surface of the conductor 340 can be substantiallylevel with a top surface of the insulator 385 in a region overlappingwith the conductor 346. Although the first conductor of the conductor340 and the second conductor of the conductor 340 are stacked in thetransistor 300, the present invention is not limited thereto. Forexample, the conductor 340 may have a single-layer structure or astacked-layer structure of three or more layers. In the case where astacked-layer structure is employed, the layers may be distinguished bynumbers corresponding to the formation order.

[Transistor 300]

As illustrated in FIGS. 21A to 21D, the transistor 300 includes aninsulator 316 over the insulator 314; a conductor 305 (a conductor 305a, a conductor 305 b, and a conductor 305 c) placed to be embedded inthe insulator 316; an insulator 322 over the insulator 316 and theconductor 305; an insulator 324 over the insulator 322; an oxide 330 aover the insulator 324; an oxide 330 b over the oxide 330 a; an oxide343 (an oxide 343 a and an oxide 343 b) over the oxide 330 b; aconductor 342 a over the oxide 343 a; an insulator 371 a over theconductor 342 a; a conductor 342 b over the oxide 343 b; an insulator371 b over the conductor 342 b; an insulator 350 (an insulator 350 a andan insulator 350 b) over the oxide 330 b; a conductor 360 (a conductor360 a and a conductor 360 b) positioned over the insulator 350 andoverlapping with part of the oxide 330 b; and an insulator 375 placed tocover the insulator 322, the insulator 324, the oxide 330 a, the oxide330 b, the oxide 343 a, the oxide 343 b, the conductor 342 a, theconductor 342 b, the insulator 371 a, and the insulator 371 b.

Hereinafter, the oxide 330 a and the oxide 330 b are collectivelyreferred to as an oxide 330 in some cases. In addition, the conductor342 a and the conductor 342 b are collectively referred to as aconductor 342 in some cases. In addition, the insulator 371 a and theinsulator 371 b are collectively referred to as an insulator 371 in somecases.

An opening that reaches the oxide 330 b is provided in the insulator 380and the insulator 375. The insulator 350 and the conductor 360 areplaced in the opening. In the channel length direction of the transistor300, the conductor 360 and the insulator 350 are provided between theinsulator 371 a, the conductor 342 a, and the oxide 343 a, and theinsulator 371 b, the conductor 342 b, and the oxide 343 b. The insulator350 includes a region in contact with a side surface of the conductor360 and a region in contact with a bottom surface of the conductor 360.

The oxide 330 preferably includes the oxide 330 a placed over theinsulator 324 and the oxide 330 b placed over the oxide 330 a. The oxide330 a under the oxide 330 b can inhibit diffusion of impurities into theoxide 330 b from the components formed below the oxide 330 a.

Although the oxide 330 has a two-layer structure of the oxide 330 a andthe oxide 330 b in the transistor 300, the present invention is notlimited thereto. For example, the oxide 330 may have a single-layerstructure of the oxide 330 b or a stacked-layer structure of three ormore layers, or the oxide 330 a and the oxide 330 b may each have astacked-layer structure.

The conductor 360 functions as a first gate (also referred to as a topgate) electrode and the conductor 305 functions as a second gate (alsoreferred to as a back gate) electrode. In addition, the insulator 350functions as a first gate insulating film, and the insulator 324 and theinsulator 322 each function as a second gate insulating film. Theconductor 342 a functions as one of a source electrode and a drainelectrode, and the conductor 342 b functions as the other of the sourceelectrode and the drain electrode. A region of the oxide 330 overlappingwith the conductor 360 at least partly functions as a channel formationregion.

The oxide 330 b includes one of the source and drain regions in a regionoverlapping with the conductor 342 a, and includes the other of thesource and drain regions in a region overlapping with the conductor 342b. The oxide 330 b includes the channel formation region (regionindicated by a shaded portion in FIG. 21B) in a region between thesource and drain regions.

The channel formation region has fewer oxygen vacancies or lowerimpurity concentration than the source and drain regions, and thus is ahigh-resistance region with a low carrier concentration. The carrierconcentration of the channel formation region is preferably lower thanor equal to 1×10¹⁸ cm⁻³, further preferably lower than 1×10¹⁷ cm⁻³,still further preferably lower than 1×10¹⁶ cm⁻³, yet further preferablylower than 1×10¹³ cm⁻³, and yet still further preferably lower than1×10¹² cm⁻³. Note that the lower limit of the carrier concentration ofthe channel formation region is not particularly limited and can be, forexample, 1×10⁻⁹ cm⁻³.

Although the channel formation region, the source region, and the drainregion are formed in the oxide 330 b in the above example, the presentinvention is not limited thereto. For example, the channel formationregion, the source region, and the drain region are formed also in theoxide 330 a in some cases.

In the transistor 300, the oxide 330 (the oxide 330 a and the oxide 330b) which includes the channel formation region preferably contains ametal oxide functioning as a semiconductor (hereinafter also referred toas oxide semiconductor).

The metal oxide functioning as a semiconductor preferably has a band gapof 2 eV or more, preferably 2.5 eV or more. The use of such a metaloxide having a wide band gap can reduce the off-state current of thetransistor.

For example, as the oxide 330, a metal oxide such as an In-M-Zn oxidecontaining indium, an element M, and zinc is used; the element M is oneor more selected from aluminum, gallium, yttrium, tin, copper, vanadium,beryllium, boron, titanium, iron, nickel, germanium, zirconium,molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten,magnesium, and the like. Alternatively, an In—Ga oxide, an In—Zn oxide,or indium oxide may be used as the oxide 330.

Here, the atomic ratio of In to the element M in the metal oxide used asthe oxide 330 b is preferably greater than that in the metal oxide usedas the oxide 330 a.

Specifically, as the oxide 330 a, a metal oxide having an atomic ratioof In:M:Zn=1:3:4 or in the vicinity thereof, or In:M:Zn=1:1:0.5 or inthe vicinity thereof may be used. As the oxide 330 b, a metal oxidehaving an atomic ratio of In:M:Zn=1:1:1 or in the vicinity thereof, orIn:M:Zn=4:2:3 or in the vicinity thereof may be used. Note that thevicinity of the atomic ratio includes ±30% of an intended atomic ratio.Gallium is preferably used as the element M.

When the metal oxide is deposited by a sputtering method, the aboveatomic ratio is not limited to the atomic ratio of the deposited metaloxide and may be the atomic ratio of a sputtering target used fordepositing the metal oxide.

When the oxide 330 a is provided under the oxide 330 b in the abovemanner, impurities and oxygen can be inhibited from diffusing into theoxide 330 b from the components formed below the oxide 330 a.

The density of defect states at the interface between the oxide 330 aand the oxide 330 b can be made low when the oxide 330 a and the oxide330 b contain the same element (as a main component) in addition tooxygen. Since the density of defect states at the interface between theoxide 330 a and the oxide 330 b can be low, the influence of interfacescattering on carrier conduction can be small and a high on-statecurrent can be obtained.

The oxide 330 a and the oxide 330 b each preferably has crystallinity.In particular, as the oxide 330 b, a c-axis-aligned crystalline oxidesemiconductor (CAAC-OS) is preferably used.

The CAAC-OS is a metal oxide having a dense structure with highcrystallinity and a small amount of impurities or defects (oxygenvacancies (Vo) or the like). In particular, after the formation of ametal oxide, heat treatment is performed at a temperature at which themetal oxide does not become a polycrystal (e.g., 400° C. to 600° C.),whereby a CAAC-OS having a dense structure with higher crystallinity canbe obtained. As the density of the CAAC-OS is increased in such amanner, diffusion of impurities or oxygen in the CAAC-OS can be furtherreduced.

By contrast, in the CAAC-OS, a reduction in electron mobility due to acrystal grain boundary is less likely to occur because it is difficultto observe a clear crystal grain boundary. Thus, a metal oxide includingthe CAAC-OS is physically stable. Accordingly, the metal oxide includingthe CAAC-OS is resistant to heat and has high reliability.

At least one of the insulators 312, 314, 371, 375, 382, and 383preferably functions as a barrier insulating film that inhibitsdiffusion of impurities such as water and hydrogen into the transistor300 from the substrate side or from above the transistor 300. Therefore,at least one of the insulators 312, 314, 371, 375, 382, and 383 ispreferably formed using an insulating material having a function ofinhibiting diffusion of impurities such as a hydrogen atom, a hydrogenmolecule, a water molecule, a nitrogen atom, a nitrogen molecule, anitrogen oxide molecule (e.g., N₂O, NO, and NO₂), and a copper atom,that is, an insulating material through which the impurities are lesslikely to pass. Alternatively, it is preferable to use an insulatingmaterial having a function of inhibiting diffusion of oxygen (e.g., atleast one of oxygen atoms, oxygen molecules, and the like), that is, aninsulating material through which the oxygen is less likely to pass.

Note that in this specification, a barrier insulating film refers to aninsulating film having a barrier property. A barrier property in thisspecification means a function of inhibiting diffusion of a particularsubstance (also referred to as a function of less easily transmittingthe substance). Alternatively, a barrier property in this specificationmeans a function of capturing or fixing (also referred to as gettering)a particular substance.

Aluminum oxide, magnesium oxide, hafnium oxide, gallium oxide, indiumgallium zinc oxide, silicon nitride, silicon nitride oxide, or the likecan be used for the insulators 312, 314, 371, 375, 382, and 383. Forexample, silicon nitride, which has a high hydrogen barrier property, ispreferably used for the insulators 312, 375, and 383. For example,aluminum oxide or magnesium oxide, which has a function of capturing orfixing more hydrogen, is preferably used for the insulators 314, 371,and 382. Accordingly, impurities such as water and hydrogen can beinhibited from diffusing to the transistor 300 side from the substrateside through the insulators 312 and 314. Furthermore, impurities such aswater and hydrogen can be inhibited from diffusing to the transistor 300side from an interlayer insulating film and the like positioned outsidethe insulator 383. In addition, oxygen contained in the insulator 324and the like can be inhibited from diffusing to the substrate sidethrough the insulators 312 and 314. Furthermore, oxygen contained in theinsulator 380 and the like can be inhibited from diffusing over thetransistor 300 through the insulator 382 and the like. In this manner,the transistor 300 is preferably surrounded by the insulators 312, 314,371, 375, 382, and 383 having a function of inhibiting diffusion ofoxygen and impurities such as water and hydrogen.

Here, an oxide having an amorphous structure is preferably used as theinsulators 312, 314, 371, 375, 382, and 383. For example, a metal oxidesuch as AlOx (x is a given number greater than 0) or MgOy (y is a givennumber greater than 0) is preferably used. In such a metal oxide havingan amorphous structure, an oxygen atom has a dangling bond and aproperty of trapping or fixing hydrogen by the dangling bond. When sucha metal oxide having an amorphous structure is used as the component ofthe transistor 300 or provided around the transistor 300, hydrogen in oraround the transistor 300 can be trapped or fixed. In particular,hydrogen contained in the channel formation region of the transistor 300is preferably trapped or fixed. When a metal oxide having an amorphousstructure is used as the component of the transistor 300 or providedaround the transistor 300, the transistor 300 and the semiconductordevice with favorable characteristics and high reliability can befabricated.

The insulators 312, 314, 371, 375, 382, and 383 each preferably have anamorphous structure, but may partly include a region with apolycrystalline structure. Alternatively, the insulators 312, 314, 371,375, 382, and 383 may each have a multilayer structure including a layerwith an amorphous structure and a layer with a polycrystallinestructure. For example, a stacked-layer structure in which a layer witha polycrystalline structure is formed over a layer with an amorphousstructure may be employed.

The insulators 312, 314, 371, 375, 382, and 383 can be formed by asputtering method, for example. Since the sputtering method does notneed to use hydrogen as a deposition gas, the hydrogen concentration inthe insulators 312, 314, 371, 375, 382, and 383 can be reduced. Notethat the deposition method is not limited to a sputtering method, and aCVD method, an MBE method, a PLD method, an ALD method, or the like canbe used as appropriate.

The insulators 316, 380, and 385 preferably have a lower dielectricconstant than the insulator 314. The use of a material having a lowdielectric constant for the interlayer insulating film can reduce theparasitic capacitance between wirings. For example, for the insulators316, 380, and 385, silicon oxide, silicon oxynitride, silicon nitrideoxide, silicon nitride, silicon oxide to which fluorine is added,silicon oxide to which carbon is added, silicon oxide to which carbonand nitrogen are added, porous silicon oxide, or the like is used asappropriate.

The conductor 305 is placed to overlap with the oxide 330 and theconductor 360. The conductor 305 is preferably provided to be embeddedin an opening formed in the insulator 316.

The conductor 305 includes the conductor 305 a, the conductor 305 b, andthe conductor 305 c. The conductor 305 a is provided in contact with abottom surface and a side wall of the opening. The conductor 305 b isprovided to be embedded in a recessed portion formed in the conductor305 a. Here, a top surface of the conductor 305 b is lower in level thantop surfaces of the conductor 305 a and the insulator 316. The conductor305 c is provided in contact with the top surface of the conductor 305 band a side surface of the conductor 305 a. Here, a top surface of theconductor 305 c is substantially level with the top surfaces of theconductor 305 a and the insulator 316. That is, the conductor 305 b issurrounded by the conductor 305 a and the conductor 305 c.

The conductor 305 a and the conductor 305 c may be formed using aconductive material that can be used for the conductor 360 a, which willbe described later. The conductor 305 b may be formed using a conductivematerial that can be used for the conductor 360 b, which will bedescribed later. Although the conductor 305 a, the conductor 305 b, andthe conductor 305 c are stacked in the transistor 300, the presentinvention is not limited thereto. For example, the conductor 305 mayhave a single-layer structure, a two-layer structure, or a stacked-layerstructure of four or more layers.

The insulators 322 and 324 each function as a gate insulating film.

The insulator 322 preferably has a function of inhibiting diffusion ofhydrogen (e.g., at least one of hydrogen atoms, hydrogen molecules, andthe like). The insulator 322 also preferably has a function ofinhibiting diffusion of oxygen (e.g., at least one of oxygen atoms andoxygen molecules). For example, the insulator 322 preferably has afunction of inhibiting diffusion of much hydrogen and/or oxygen comparedto the insulator 324.

As the insulator 322, an insulator containing an oxide of aluminumand/or hafnium, which is an insulating material, is preferably used. Asthe insulator, aluminum oxide, hafnium oxide, an oxide containingaluminum and hafnium (hafnium aluminate), or the like is preferablyused. Alternatively, as the insulator 322, a barrier insulating filmthat can be used for the above-described insulator 314 and the like maybe used.

For example, silicon oxide or silicon oxynitride can be used asappropriate for the insulator 324. When the insulator containing oxygenis provided in contact with the oxide 330, oxygen vacancies in the oxide330 can be reduced, leading to an improvement in reliability of thetransistor 300. The insulator 324 is preferably processed into an islandshape to overlap with the oxide 330 a. In that case, the insulator 375is in contact with a side surface of the insulator 324 and a top surfaceof the insulator 322. Accordingly, the insulator 324 and the insulator380 can be separated from each other by the insulator 375, so thatoxygen contained in the insulator 380 can be inhibited from diffusinginto the insulator 324 and serving as excess oxygen in the insulator324.

Note that the insulators 322 and 324 may each have a stacked-layerstructure of two or more layers. In that case, the stacked layers arenot necessarily formed of the same material and may be formed ofdifferent materials. Although the insulator 324 is formed into an islandshape to overlap with the oxide 330 a in FIG. 21B and the like, thepresent invention is not limited thereto. As long as the amount ofoxygen contained in the insulator 324 can be adjusted appropriately, theinsulator 324 is not necessarily patterned, like the insulator 322.

The oxides 343 a and 343 b are provided over the oxide 330 b. The oxides343 a and 343 b are provided apart from each other with the conductor360 therebetween. The oxide 343 (the oxide 343 a and the oxide 343 b)preferably has a function of inhibiting oxygen transmission. When theoxide 343, which has a function of inhibiting oxygen transmission, isprovided between the oxide 330 b and the conductor 342 functioning asthe source electrode or the drain electrode, the electrical resistancebetween the conductor 342 and the oxide 330 b can be reduced, which ispreferable. In the case where the electrical resistance between theconductor 342 and the oxide 330 b can be sufficiently reduced, the oxide343 is not necessarily provided.

A metal oxide containing the element M may be used as the oxide 343. Inparticular, aluminum, gallium, yttrium, or tin is preferably used as theelementM. The concentration of the element M in the oxide 343 ispreferably higher than that in the oxide 330 b. Alternatively, galliumoxide may be used as the oxide 343. A metal oxide such as an In-M-Znoxide may be used as the oxide 343. Specifically, the atomic ratio ofthe element Mto In in the metal oxide used as the oxide 343 ispreferably higher than that in the metal oxide used as the oxide 330 b.The thickness of the oxide 343 ranges preferably from 0.5 nm to 5 nm,further preferably from 1 nm to 3 nm, still further preferably from 1 nmto 2 nm.

It is preferable that the conductor 342 a be provided in contact with atop surface of the oxide 343 a, and the conductor 342 b be provided incontact with a top surface of the oxide 343 b. The conductors 342 a and342 b function as the source electrode and the drain electrode of thetransistor 300.

For the conductor 342 (the conductor 342 a and the conductor 342 b), forexample, a nitride containing tantalum, a nitride containing titanium, anitride containing molybdenum, a nitride containing tungsten, a nitridecontaining tantalum and aluminum, a nitride containing titanium andaluminum, or the like is preferably used. In one embodiment of thepresent invention, a nitride containing tantalum is particularlypreferable. As another example, ruthenium oxide, ruthenium nitride, anoxide containing strontium and ruthenium, or an oxide containinglanthanum and nickel may be used. These materials are preferable becausethey are a conductive material that is not easily oxidized or a materialthat maintains the conductivity even when absorbing oxygen.

No curved surface is preferably formed between the side surface and thetop surface of the conductor 342. Without the curved surface, theconductor 342 can have a large cross-sectional area in the channel widthdirection as illustrated in FIG. 21D. Accordingly the conductivity ofthe conductor 342 and the on-state current of the transistor 300 can beincreased.

The insulator 371 a is provided in contact with a top surface of theconductor 342 a, and the insulator 371 b is provided in contact with atop surface of the conductor 342 b.

The insulator 375 is provided in contact with the top surface of theinsulator 322, the side surface of the insulator 324, a side surface ofthe oxide 330 a, a side surface of the oxide 330 b, a side surface ofthe oxide 343, a side surface of the conductor 342, and the side surfaceand top surface of the insulator 371. The insulator 375 has an openingin a region where the insulator 350 and the conductor 360 are provided.

The insulators 314, 371, and 375, which have a function of capturingimpurities such as hydrogen, are provided in a region interposed betweenthe insulator 312 and the insulator 375, whereby impurities such ashydrogen contained in the insulator 324, the insulator 316, or the likecan be captured and the amount of hydrogen in the region can be keptconstant. In that case, the insulators 314, 371, and 375 preferablycontain aluminum oxide with an amorphous structure.

The insulator 350 includes the insulator 350 a and the insulator 350 bover the insulator 350 a, and functions as a gate insulating film. Theinsulator 350 a is preferably placed in contact with a top surface ofthe oxide 330 b, the side surface of the oxide 343, the side surface ofthe conductor 342, the side surface of the insulator 371, a side surfaceof the insulator 375, and aside surface of the insulator 380. Thethickness of the insulator 350 is preferably greater than or equal to 1nm and less than or equal to 20 nm.

The insulator 350 a can be formed using silicon oxide, siliconoxynitride, silicon nitride oxide, silicon nitride, silicon oxide towhich fluorine is added, silicon oxide to which carbon is added, siliconoxide to which carbon and nitrogen are added, porous silicon oxide, orthe like. In particular, silicon oxide and silicon oxynitride, whichhave thermal stability, are preferable. As in the insulator 324, theconcentration of impurities such as water and hydrogen in the insulator350 a is preferably reduced.

It is preferable that the insulator 350 a be formed using an insulatorfrom which oxygen is released by heating and the insulator 350 b beformed using an insulator having a function of inhibiting diffusion ofoxygen. Owing to this structure, diffusion of oxygen contained in theinsulator 350 a into the conductor 360 can be inhibited. That is, areduction in the amount of oxygen supplied to the oxide 330 can beinhibited. Moreover, oxidation of the conductor 360 due to oxygencontained in the insulator 350 a can be inhibited. The insulator 350 bcan be formed using a material similar to that for the insulator 322.

Specifically, for the insulator 350 b, a metal oxide containing one ormore of hafnium, aluminum, gallium, yttrium, zirconium, tungsten,titanium, tantalum, nickel, germanium, magnesium, and the like or ametal oxide that can be used as the oxide 330 can be used. Inparticular, an insulator containing an oxide of one or both of aluminumand hafnium is preferably used. As the insulator, aluminum oxide,hafnium oxide, an oxide containing aluminum and hafnium (hafniumaluminate), or the like is preferably used. The thickness of theinsulator 350 b is preferably greater than or equal to 0.5 nm and lessthan or equal to 3.0 nm, further preferably greater than or equal to 1.0nm and less than or equal to 1.5 nm.

Note that although the insulator 350 has a stacked-layer structure oftwo layers in FIGS. 21B and 21C, the present invention is not limitedthereto. The insulator 350 may have a single-layer structure or astacked-layer structure of three or more layers.

The conductor 360 is provided over the insulator 350 b and functions asa first gate electrode of the transistor 300. The conductor 360preferably includes the conductor 360 a and the conductor 360 b over theconductor 360 a. For example, the conductor 360 a is preferablypositioned to cover the bottom surface and the side surface of theconductor 360 b. As illustrated in FIGS. 21B and 21C, a top surface ofthe conductor 360 is substantially aligned with a top surface of theinsulator 350. Although the conductor 360 has a two-layer structure ofthe conductor 360 a and the conductor 360 b in FIGS. 21B and 21C, theconductor 360 may have a single-layer structure or a stacked-layerstructure of three or more layers.

The conductor 360 a is preferably formed using a conductive materialhaving a function of inhibiting diffusion of impurities such as ahydrogen atom, a hydrogen molecule, a water molecule, a nitrogen atom, anitrogen molecule, a nitrogen oxide molecule, and a copper atom.Alternatively, the conductor 360 a is preferably formed using aconductive material having a function of inhibiting diffusion of oxygen(e.g., at least one of oxygen atoms and oxygen molecules).

When the conductor 360 a has a function of inhibiting diffusion ofoxygen, the conductivity of the conductor 360 b can be prevented frombeing lowered because of oxidization of the conductor 360 b due tooxygen in the insulator 350. As the conductive material having afunction of inhibiting diffusion of oxygen, for example, titanium,titanium nitride, tantalum, tantalum nitride, ruthenium, or rutheniumoxide is preferably used.

The conductor 360 also functions as a wiring and thus is preferably aconductor having high conductivity. For example, a conductive materialcontaining tungsten, copper, or aluminum as its main component can beused for the conductor 360 b. The conductor 360 b may have astacked-layer structure, for example, a stacked-layer structure of anyof the above conductive materials and titanium or titanium nitride.

In the transistor 300, the conductor 360 is formed in a self-alignedmanner to fill an opening formed in the insulator 380 and the like. Inthis manner, the conductor 360 can surely be provided in a regionbetween the conductor 342 a and the conductor 342 b without alignment.

As illustrated in FIG. 21C, in the channel width direction of thetransistor 300, the bottom surface of the conductor 360 not overlappingwith the oxide 330 b is preferably lower in level than the bottomsurface of the oxide 330 b, with the level of the bottom surface of theinsulator 322 as a reference. When the conductor 360 functioning as thegate electrode covers the side and top surfaces of the channel formationregion in the oxide 330 b with the insulator 350 and the liketherebetween, the electric field of the conductor 360 is likely toaffect the entire channel formation region in the oxide 330 b. Hence,the transistor 300 can have a higher on-state current and higherfrequency characteristics. With the level of the bottom surface of theinsulator 322 as a reference, a distance between the bottom surface ofthe conductor 360 and the bottom surface of the oxide 330 b in a regionwhere the conductor 360 does not overlap with the oxides 330 a and 330 bis greater than or equal to 0 nm and less than or equal to 100 nm,preferably greater than or equal to 3 nm and less than or equal to 50nm, and further preferably greater than or equal to 5 nm and less thanor equal to 20 nm.

The insulator 380 is provided over the insulator 375, and an opening isformed in a region where the insulator 350 and the conductor 360 areprovided. The top surface of the insulator 380 may be planarized. Inthis case, it is preferable that the top surface of the insulator 380 besubstantially aligned with the top surfaces of the insulator 350 and theconductor 360.

The insulator 382 is provided in contact with the top surfaces of theinsulator 380, the insulator 350, and conductor 360. The insulator 382preferably functions as a barrier insulating film that inhibitsimpurities such as water and hydrogen from diffusing into the insulator380 from the above and also has a function of capturing impurities suchas hydrogen. The insulator 382 also preferably functions as a barrierinsulating film for inhibiting transmission of oxygen. As the insulator382, for example, an insulator such as aluminum oxide can be used. Theinsulator 382, which has a function of capturing impurities such ashydrogen, is provided in contact with the insulator 380 in a regioninterposed between the insulator 312 and the insulator 383, wherebyimpurities such as hydrogen contained in the insulator 380 and the likecan be captured and the amount of hydrogen in the region can be keptconstant. It is particularly preferable to use aluminum oxide having anamorphous structure as the insulator 382 because hydrogen can besufficiently trapped or fixed in some cases. Accordingly, the transistor300 and the semiconductor device with favorable characteristics and highreliability can be fabricated.

The conductors 340 a and 340 b are preferably formed using a conductivematerial containing tungsten, copper, or aluminum as its main component.The conductors 340 a and 340 b may have a stacked-layer structure. Inthe case where the conductor 340 has a stacked-layer structure, theconductor in contact with the insulator 341 is preferably formed using aconductive material having a function of inhibiting the transmission ofoxygen and impurities such as water and hydrogen. For example, any ofthe above conductive materials that can be used for the conductor 360 amay be used.

An insulator such as silicon nitride, aluminum oxide, or silicon nitrideoxide may be used as the insulators 341 a and 341 b, for example. Sincethe insulators 341 a and 341 b are provided in contact with theinsulators 383, 382, and 371, impurities such as water and hydrogencontained in the insulator 380 or the like can be inhibited fromentering the oxide 330 through the conductors 340 a and 340 b.

The conductor 346 (the conductor 346 a and the conductor 346 b)functioning as a wiring may be provided in contact with the top surfacesof the conductors 340 a and 340 b. The conductor 346 is preferablyformed using a conductive material containing tungsten, copper, oraluminum as its main component. The conductor may have a stacked-layerstructure, for example, a stack of any of the above conductive materialsand titanium or titanium nitride. Note that the conductor may be formedto be embedded in an opening in an insulator.

Accordingly, a semiconductor device having favorable electricalcharacteristics can be provided. A highly reliable semiconductor devicecan be provided. A semiconductor device that can be miniaturized orhighly integrated can be provided. A semiconductor device with low powerconsumption can be provided.

Note that this embodiment can be combined with any of the otherembodiments in this specification as appropriate.

Embodiment 10

Described in this embodiment is a metal oxide (hereinafter also referredto as an oxide semiconductor) applicable to an OS transistor describedin the above embodiment.

A metal oxide preferably contains at least indium or zinc. Inparticular, indium and zinc are preferably contained. In addition,aluminum, gallium, yttrium, tin, or the like is preferably contained.Furthermore, one or more elements selected from boron, titanium, iron,nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium,hafnium, tantalum, tungsten, magnesium, cobalt, and the like may becontained.

<Classification of Crystal Structures>

First, the classification of the crystal structures of an oxidesemiconductor will be described with reference to FIG. 22A. FIG. 22A isa diagram showing the classification of crystal structures of an oxidesemiconductor, typically IGZO (a metal oxide containing In, Ga, and Zn).

As shown in FIG. 22A, an oxide semiconductor is roughly classified into“Amorphous”, “Crystalline”, and “Crystal”. The term “Amorphous” includesa completely amorphous structure. The term “Crystalline” includesc-axis-aligned crystalline (CAAC), nanocrystalline (nc), andcloud-aligned composite (CAC) structures. Note that the term“Crystalline” excludes single crystal, poly crystal, and completelyamorphous structures. The term “Crystal” includes single crystal andpoly crystal structures.

Note that the structures in the thick frame in FIG. 22A are in anintermediate state between “Amorphous” and “Crystal”, and belong to anew crystalline phase. That is, these structures are completelydifferent from “Amorphous”, which is energetically unstable, and“Crystal”.

A crystal structure of a film or a substrate can be analyzed with anX-ray diffraction (XRD) spectrum. FIG. 22B shows an XRD spectrum, whichis obtained by grazing-incidence XRD (GIXD) measurement, of a CAAC-IGZOfilm classified into “Crystalline”. Note that a GIXD method is alsoreferred to as a thin film method or a Seemann-Bohlin method. The XRDspectrum that is shown in FIG. 22B and obtained by GIXD measurement ishereinafter simply referred to as an XRD spectrum. The CAAC-IGZO film inFIG. 22B has an atomic ratio of In:Ga:Zn=4:2:3 or a neighborhoodthereof. The CAAC-IGZO film in FIG. 22B has a thickness of 500 nm.

As shown in FIG. 22B, a clear peak indicating crystallinity is observedin the XRD spectrum of the CAAC-IGZO film. Specifically, a peakindicating c-axis alignment is observed at around 2θ=31° in the XRDspectrum of the CAAC-IGZO film. As shown in FIG. 22B, the peak at around2θ=31° is asymmetric with the angle at which the peak intensity isobserved as the axis.

A crystal structure of a film or a substrate can also be evaluated witha diffraction pattern obtained by a nanobeam electron diffraction (NBED)method (such a pattern is also referred to as a nanobeam electrondiffraction pattern). FIG. 22C shows a diffraction pattern of theCAAC-IGZO film. FIG. 22C shows a diffraction pattern obtained by theNBED method in which an electron beam is incident in the directionparallel to the substrate. The CAAC-IGZO film in FIG. 22C has an atomicratio of In:Ga:Zn=4:2:3 or a neighborhood thereof. In the nanobeamelectron diffraction method, electron diffraction is performed with aprobe diameter of 1 nm.

As shown in FIG. 22C, a plurality of spots indicating c-axis alignmentare observed in the diffraction pattern of the CAAC-IGZO film.

<<Structure of Oxide Semiconductor>>

Oxide semiconductors might be classified in a manner different from theone in FIG. 22A when classified in terms of the crystal structure. Oxidesemiconductors are classified into a single crystal oxide semiconductorand a non-single-crystal oxide semiconductor, for example. Examples ofthe non-single-crystal oxide semiconductor include the above-describedCAAC and nc-OS. Other examples of the non-single-crystal oxidesemiconductor include a polycrystalline oxide semiconductor, anamorphous-like oxide semiconductor (a-like OS), and an amorphous oxidesemiconductor.

Next, the CAAC-OS, nc-OS, and a-like OS will be described in detail.

[CAAC-OS]

The CAAC-OS is an oxide semiconductor that has a plurality of crystalregions each of which has c-axis alignment in a particular direction.Note that the particular direction refers to the film thicknessdirection of a CAAC-OS film, the normal direction of the surface wherethe CAAC-OS film is formed, or the normal direction of the surface ofthe CAAC-OS film. The crystal region refers to a region having aperiodic atomic arrangement. When an atomic arrangement is regarded as alattice arrangement, the crystal region also refers to a region with auniform lattice arrangement. The CAAC-OS has a region where a pluralityof crystal regions are connected in the a-b plane direction, and theregion has distortion in some cases. Note that distortion refers to aportion where the direction of a lattice arrangement changes between aregion with a uniform lattice arrangement and another region with auniform lattice arrangement in a region where a plurality of crystalregions are connected. That is, the CAAC-OS is an oxide semiconductorhaving c-axis alignment and having no clear alignment in the a-b planedirection.

Note that each of the plurality of crystal regions is formed of one ormore fine crystals (crystals each of which has a maximum diameter ofless than 10 nm). In the case where the crystal region is formed of onefine crystal, the maximum diameter of the crystal region is less than 10nm. In the case where the crystal region is formed of a large number offine crystals, the size of the crystal region may be approximatelyseveral tens of nanometers.

In the case of an In-M-Zn oxide (the element M is one or more ofaluminum, gallium, yttrium, tin, titanium, and the like), the CAAC-OStends to have a layered crystal structure (also referred to as astacked-layer structure) in which a layer containing indium (In) andoxygen (hereinafter, an In layer) and a layer containing the element M,zinc (Zn), and oxygen (hereinafter, an (M,Zn) layer) are stacked. Indiumand the element M can be replaced with each other. Therefore, indium maybe contained in the (M,Zn) layer. In addition, the element M may becontained in the In layer. Note that Zn may be contained in the Inlayer. Such a layered structure is observed as a lattice image in ahigh-resolution TEM image, for example.

When the CAAC-OS film is subjected to structural analysis byout-of-plane XRD measurement with an XRD apparatus using θ/2θ scanning,for example, a peak indicating c-axis alignment is detected at or around2θ=31°. Note that the position of the peak indicating c-axis alignment(the value of 2θ) may change depending on the kind, composition, or thelike of the metal element contained in the CAAC-OS.

For example, a plurality of bright spots are observed in the electrondiffraction pattern of the CAAC-OS film. Note that one spot and anotherspot are observed point-symmetrically with a spot of the incidentelectron beam passing through a sample (also referred to as a directspot) as the symmetric center.

When the crystal region is observed from the particular direction, alattice arrangement in the crystal region is basically a hexagonallattice arrangement; however, a unit lattice is not always a regularhexagon and is a non-regular hexagon in some cases. A pentagonal latticearrangement, a heptagonal lattice arrangement, and the like are includedin the distortion in some cases. Note that a clear grain boundary cannotbe observed even in the vicinity of the distortion in the CAAC-OS. Thatis, formation of a grain boundary is inhibited by the distortion of alattice arrangement. This is probably because the CAAC-OS can toleratedistortion owing to a low density of arrangement of oxygen atoms in thea-b plane direction, an interatomic bond distance changed bysubstitution of a metal atom, and the like.

A crystal structure in which a clear grain boundary is observed is whatis called a polycrystal structure. It is highly probable that the grainboundary becomes a recombination center and traps carriers and thusdecreases the on-state current and field-effect mobility of atransistor, for example. Thus, the CAAC-OS in which no clear grainboundary is observed is one of crystalline oxides having a crystalstructure suitable for a semiconductor layer of a transistor. Note thatZn is preferably contained to form the CAAC-OS. For example, an In—Znoxide and an In-Ga—Zn oxide are suitable because they can inhibitgeneration of a grain boundary as compared with an In oxide.

The CAAC-OS is an oxide semiconductor with high crystallinity in whichno clear grain boundary is observed. Thus, in the CAAC-OS, a reductionin electron mobility due to the grain boundary is less likely to occur.Entry of impurities, formation of defects, or the like might decreasethe crystallinity of an oxide semiconductor. This means that the CAAC-OScan be referred to as an oxide semiconductor having small amounts ofimpurities and defects (e.g., oxygen vacancies). Therefore, an oxidesemiconductor including the CAAC-OS is physically stable. Accordingly,the oxide semiconductor including the CAAC-OS is resistant to heat andhas high reliability. In addition, the CAAC-OS is stable with respect tohigh temperatures in the manufacturing process (i.e., thermal budget).Accordingly, the use of the CAAC-OS for the OS transistor can extend adegree of freedom of the manufacturing process.

[nc-OS]

In the nc-OS, a microscopic region (e.g., a region with a size greaterthan or equal to 1 nm and less than or equal to 10 nm, in particular, aregion with a size greater than or equal to 1 nm and less than or equalto 3 nm) has a periodic atomic arrangement. In other words, the nc-OSincludes a fine crystal. Note that the size of the fine crystal is, forexample, greater than or equal to 1 nm and less than or equal to 10 nm,particularly greater than or equal to 1 nm and less than or equal to 3nm; thus, the fine crystal is also referred to as a nanocrystal. Thereis no regularity of crystal orientation between different nanocrystalsin the nc-OS. Hence, the orientation in the whole film is not observed.Accordingly, in some cases, the nc-OS cannot be distinguished from ana-like OS or an amorphous oxide semiconductor, depending on an analysismethod. For example, when an nc-OS film is subjected to structuralanalysis by out-of-plane XRD measurement with an XRD apparatus usingθ/2θ scanning, a peak indicating crystallinity is not observed.Furthermore, a halo pattern is shown in a selected-area electrondiffraction pattern of the nc-OS film obtained using an electron beamhaving a probe diameter larger than the diameter of a nanocrystal (e.g.,larger than or equal to 50 nm). Meanwhile, in some cases, a plurality ofspots in a ring-like region with a direct spot as the center areobserved in a nanobeam electron diffraction pattern of the nc-OS filmobtained using an electron beam with a probe diameter nearly equal to orsmaller than the diameter of a nanocrystal (e.g., 1 nm or larger and 30nm or smaller).

[A-Like OS]

The a-like OS is an oxide semiconductor having a structure between thoseof the nc-OS and the amorphous oxide semiconductor. The a-like OS has avoid or a low-density region. That is, the a-like OS has lowercrystallinity than the nc-OS and the CAAC-OS. Moreover, the a-like OShas higher hydrogen concentration than the nc-OS and the CAAC-OS.

<<Composition of Oxide Semiconductor>>

Next, the CAC-OS will be described in detail. Note that the CAC-OSrelates to the material composition.

[CAC-OS]

The CAC-OS has, for example, a composition in which elements included ina metal oxide are unevenly distributed. Materials including unevenlydistributed elements each have a size greater than or equal to 0.5 nmand less than or equal to 10 nm, preferably greater than or equal to 1nm and less than or equal to 3 nm, or a similar size. Note that in thefollowing description of a metal oxide, a state in which one or moretypes of metal elements are unevenly distributed and regions includingthe metal element(s) are mixed is referred to as a mosaic pattern or apatch-like pattern. The regions each have a size greater than or equalto 0.5 nm and less than or equal to 10 nm, preferably greater than orequal to 1 nm and less than or equal to 3 nm, or a similar size.

In addition, the CAC-OS has a composition in which materials areseparated into a first region and a second region to form a mosaicpattern, and the first regions are distributed in the film. Thiscomposition is hereinafter also referred to as a cloud-like composition.That is, the CAC-OS is a composite metal oxide having a composition inwhich the first regions and the second regions are mixed.

Note that the atomic ratios of In, Ga, and Zn to the metal elementscontained in the CAC-OS in an In-Ga—Zn oxide are denoted by [In], [Ga],and [Zn], respectively. For example, the first region in the CAC-OS inthe In-Ga—Zn oxide has [In] higher than that in the composition of theCAC-OS film. Moreover, the second region in the CAC-OS in the In-Ga—Znoxide has [Ga] higher than that in the composition of the CAC-OS film.For example, the first region has higher [In] and lower [Ga] than thesecond region. Moreover, the second region has higher [Ga] and lower[In] than the first region.

Specifically, the first region includes indium oxide, indium zinc oxide,or the like as its main component. The second region includes galliumoxide, gallium zinc oxide, or the like as its main component. That is,the first region can be referred to as a region containing In as itsmain component. The second region can be referred to as a regioncontaining Ga as its main component.

Note that a clear boundary between the first region and the secondregion cannot be observed in some cases.

For example, energy dispersive X-ray spectroscopy (EDX) is used toobtain EDX mapping, and according to the EDX mapping, the CAC-OS in theIn-Ga—Zn oxide has a composition in which the region containing In asits main component (the first region) and the region containing Ga asits main component (the second region) are unevenly distributed andmixed.

In the case where the CAC-OS is used for a transistor, a switchingfunction (on/off switching function) can be given to the CAC-OS owing tothe complementary action of the conductivity derived from the firstregion and the insulating property derived from the second region. Thatis, the CAC-OS has a conducting function in part of the material and hasan insulating function in another part of the material; as a whole, theCAC-OS has a function of a semiconductor. Separation of the conductingfunction and the insulating function can maximize each function.Accordingly, when the CAC-OS is used for a transistor, high on-statecurrent (I_(on)), high field-effect mobility (μ), and excellentswitching operation can be achieved.

An oxide semiconductor can have any of various structures that showvarious different properties. Two or more of the amorphous oxidesemiconductor, the polycrystalline oxide semiconductor, the a-like OS,the CAC-OS, the nc-OS, and the CAAC-OS may be included in an oxidesemiconductor of one embodiment of the present invention.

<Transistor Including Oxide Semiconductor>

Next, a transistor including the above oxide semiconductor is described.

When the oxide semiconductor is used for a transistor, the transistorcan have high field-effect mobility. In addition, the transistor canhave high reliability.

An oxide semiconductor having a low carrier concentration is preferablyused for of the transistor. For example, the carrier concentration of anoxide semiconductor is lower than or equal to 1×10¹⁷ cm⁻³, preferablylower than or equal to 1×10¹⁵ cm⁻³, further preferably lower than orequal to 1×10¹³ cm⁻³, still further preferably lower than or equal to1×10¹¹ cm⁻³, yet further preferably lower than 1×10¹⁰ cm⁻³, and higherthan or equal to 1×10⁻⁹ cm⁻³. In order to reduce the carrierconcentration of an oxide semiconductor film, the impurity concentrationin the oxide semiconductor film is reduced so that the density of defectstates can be reduced. In this specification and the like, a state witha low impurity concentration and a low density of defect states isreferred to as a highly purified intrinsic or substantially highlypurified intrinsic state. Note that an oxide semiconductor having a lowcarrier concentration may be referred to as a highly purified intrinsicor substantially highly purified intrinsic oxide semiconductor.

A highly purified intrinsic or substantially highly purified intrinsicoxide semiconductor film has a low density of defect states andaccordingly has a low density of trap states in some cases.

Charges trapped by the trap states in an oxide semiconductor take a longtime to be released and may behave like fixed charges. A transistorwhose channel formation region is formed in an oxide semiconductorhaving a high density of trap states has unstable electricalcharacteristics in some cases.

In order to obtain stable electrical characteristics of the transistor,it is effective to reduce the impurity concentration in the oxidesemiconductor. In order to reduce the impurity concentration in theoxide semiconductor, the impurity concentration in a film that isadjacent to the oxide semiconductor is preferably reduced. Examples ofimpurities include hydrogen, nitrogen, alkali metal, alkaline earthmetal, iron, nickel, and silicon.

<Impurities>

The influence of impurities in the oxide semiconductor is described.

When silicon or carbon, which is a Group 14 element, is contained in anoxide semiconductor, defect states are formed in the oxidesemiconductor. Thus, the concentration of silicon or carbon in the oxidesemiconductor and in the vicinity of an interface with the oxidesemiconductor (the concentration measured by secondary ion massspectrometry (SIMS)) is lower than or equal to 2×10¹⁸ atoms/cm³,preferably lower than or equal to 2×10¹⁷ atoms/cm³.

When the oxide semiconductor contains alkali metal or alkaline earthmetal, defect states are formed and carriers are generated in somecases. Accordingly, a transistor including an oxide semiconductor thatcontains alkali metal or alkaline earth metal tends to have normally-oncharacteristics. Thus, the concentration of alkali metal or alkalineearth metal in the oxide semiconductor, which is measured by SIMS, islower than or equal to 1×10¹⁸ atoms/cm³, preferably lower than or equalto 2×10¹⁶ atoms/cm³.

An oxide semiconductor containing nitrogen easily becomes n-type bygeneration of electrons serving as carriers and an increase in carrierconcentration. A transistor including an oxide semiconductor thatcontains nitrogen as the semiconductor tends to have normally-oncharacteristics. When nitrogen is contained in the oxide semiconductor,a trap state is sometimes formed. This might make the electricalcharacteristics of the transistor unstable. Thus, the concentration ofnitrogen in the channel formation region using the oxide semiconductor,which is measured by SIMS, is lower than 5×10¹⁹ atoms/cm³, preferablylower than or equal to 5×10¹⁸ atoms/cm³, further preferably lower thanor equal to 1×10¹⁸ atoms/cm³, still further preferably lower than orequal to 5×10¹⁷ atoms/cm³.

Hydrogen contained in an oxide semiconductor reacts with oxygen bondedto a metal atom to be water, and thus causes an oxygen vacancy in somecases. Entry of hydrogen into the oxygen vacancy generates an electronserving as a carrier in some cases. Furthermore, some hydrogen may reactwith oxygen bonded to a metal atom and generate an electron serving as acarrier. Thus, a transistor including an oxide semiconductor thatcontains hydrogen tends to have normally-on characteristics. For thisreason, hydrogen in the oxide semiconductor is preferably reduced asmuch as possible. Specifically, the hydrogen concentration in the oxidesemiconductor, which is measured by SIMS, is lower than 1×10²⁰atoms/cm³, preferably lower than 1×10¹⁹ atoms/cm³, further preferablylower than 5×10¹⁸ atoms/cm³, still further preferably lower than 1×10¹⁸atoms/cm³.

When an oxide semiconductor with sufficiently reduced impurities is usedfor a channel formation region in a transistor, the transistor can havestable electrical characteristics.

Note that this embodiment can be combined with any of the otherembodiments in this specification as appropriate.

Embodiment 11

In this embodiment, a structure example of an electronic deviceincluding the functional panel of one embodiment of the presentinvention will be described.

FIG. 24A is a perspective view of a glasses-type electronic device 5700.The electronic device 5700 includes a pair of display panels 5701, apair of housings 5702, a pair of optical members 5703, a pair of wearingportions 5704, a frame 5707, a nose pad 5708, and the like.

The electronic device 5700 can project an image displayed on the displaypanel 5701 onto a display region 5706 of the optical member 5703. Sincethe optical members 5703 have a light-transmitting property, a user cansee images displayed on the display regions 5706, which are superimposedon transmission images seen through the optical members 5703. Thus, theelectronic device 5700 is an electronic device capable of AR display.

One or both of the housings 5702 may be provided with a camera capableof taking an image of what lies in front thereof. The housing 5702 mayhave a wireless communication device, in which case a video signal orthe like can be supplied to the housing 5702 by the wirelesscommunication device. Instead of or in addition to the wirelesscommunication device, a connector that can be connected to a cable forsupplying a video signal or a power supply potential may be provided.Furthermore, when the housing 5702 is provided with an accelerationsensor such as a gyroscope sensor, the orientation of the user's headcan be detected and an image corresponding to the orientation can bedisplayed on the display region 5706.

One or both of the housings 5702 may be provided with a processor. Theprocessor has a function of controlling the components of the electronicdevice 5700, such as a camera, a wireless communication device, and thepair of display panels 5701, a function of generating an image, and thelike. The processor may have a function of generating a synthesizedimage for AR display.

Furthermore, data communication with an external device can be performedby the wireless communication device. For example, when data transmittedfrom the outside is output to the processor, the processor can generateimage data for AR display on the basis of the data. Examples of the datatransmitted from the outside include, in addition to image data, dataincluding biological information transmitted from a biological sensordevice or the like.

Next, a method for projecting an image on the display region 5706 of theelectronic device 5700 is described with reference to FIG. 24B. Thedisplay panel 5701 is provided inside the housing 5702. Furthermore, areflective plate 5712 is provided in the optical member 5703, and areflective surface 5713 functioning as a half mirror is provided in aportion corresponding to the display region 5706 of the optical member5703.

Light 5715 emitted from the display panel 5701 is reflected by thereflective plate 5712 to the optical member 5703 side. In the opticalmember 5703, the light 5715 is fully reflected repeatedly by surfaces ofan edge portion of the optical member 5703 and reaches the reflectivesurface 5713, whereby an image is projected on the reflective surface5713. Accordingly, the user can see both the light 5715 reflected by thereflective surface 5713 and transmitted light 5716 that passes throughthe optical member 5703 (including the reflective surface 5713).

FIGS. 24A and 24B show an example in which the reflective plate 5712 andthe reflective surface 5713 each have a curved surface. This structurecan increase optical design flexibility and reduce the thickness of theoptical member 5703, compared to the case where the reflective plate5712 and the reflective surface 5713 are flat. Note that the reflectiveplate 5712 and the reflective surface 5713 may be flat.

The reflective plate 5712 can be a component having a mirror surface andpreferably has high reflectance. As the reflective surface 5713, a halfmirror utilizing reflection of a metal film may be used, but the use ofa total-reflection prism or the like can increase the transmittance ofthe transmitted light 5716.

The housing 5702 may include a lens between the display panel 5701 andthe reflective plate 5712. In this case, the housing 5702 preferablyincludes a mechanism for adjusting the distance and angle between thelens and the display panel 5701, in which case the focus can be adjustedand images can be zoomed in and out. One or both of the lens and thedisplay panel 5701 is preferably configured to be movable in theoptical-axis direction, for example.

The housing 5702 preferably includes a mechanism capable of adjustingthe angle of the reflective plate 5712. The position of the displayregion 5706 where images are displayed can be changed by changing theangle of the reflective plate 5712.

Thus, the display region 5706 can be placed at the most appropriateposition in accordance with the position of the user's eye.

Furthermore, the housing 5702 is preferably provided with a battery 5717and a wireless power supply module 5718. With the battery 5717, theelectronic device 5700 can be used without being connected to a battery,and thus can have higher convenience. In addition, the wireless powersupply module 5718 enables wireless charging, leading to higherconvenience and higher design property. Furthermore, the wireless powersupply module 5718 can reduce the risk of malfunction due to a defectivecontact or the like compared to the case of wired charging through aconnector or the like, leading to higher reliability of the electronicdevice 5700.

The housing 5702 is provided with a touch sensor module 5719. The touchsensor module 5719 has a function of detecting a touch on the outersurface of the housing 5702. FIG. 24B illustrates a state where theouter surface of the housing 5702 is touched by a finger 5720. Detectinga tap or slide operation by a user with the touch sensor module 5719enables a variety of processings. For example, a video can be paused orrestarted by a tap operation, or can be fast-forwarded or fast-reversedby a slide operation. Furthermore, providing the touch sensor module5719 for each of the housings 5702 enables more kinds of operations.

A variety of touch sensors can be used for the touch sensor module 5719.For example, any of touch sensors of the following types can be used: acapacitive type, a resistive type, an infrared type, an electromagneticinduction type, a surface acoustic wave type, and an optical type. Inparticular, a capacitive touch sensor or an optical sensor is preferablyused for the touch sensor module 5719.

In the case of using an optical touch sensor, a photoelectric conversionelement can be used as a light-receiving element. The photoelectricconversion element includes an inorganic semiconductor or an organicsemiconductor in its active layer, for example.

The display device or the functional panel of one embodiment of thepresent invention can be used for the display panel 5701. Thus, theelectronic device 5700 capable of extremely-high-resolution display canbe provided.

At least part of this embodiment can be implemented in combination withany of the other embodiments described in this specification asappropriate.

When this specification and the like explicitly states that X and Y areconnected, the case where X and Y are electrically connected, the casewhere X and Y are functionally connected, and the case where X and Y aredirectly connected are regarded as being disclosed in this specificationand the like. Accordingly, without limitation to a predeterminedconnection relation, for example, a connection relation shown indrawings or text, another connection relation is regarded as beingdisclosed in the drawings or the text.

Here, X and Y each denote an object (e.g., a device, an element, acircuit, a wiring, an electrode, a terminal, a conductive film, or alayer).

Examples of the case where X and Y are directly connected include thecase where an element that allows electrical connection between X and Y(e.g., a switch, a transistor, a capacitor, an inductor, a resistor, adiode, a display element, a light-emitting element, or a load) is notconnected between X and Y, and the case where X and Y are connectedwithout the element that allows electrical connection between X and Yprovided therebetween.

For example, in the case where X and Y are electrically connected, atleast one element that enables electrical connection between X and Y(e.g., a switch, a transistor, a capacitor, an inductor, a resistor, adiode, a display element, a light-emitting element, or a load) can beconnected between X and Y. Note that a switch is controlled to be turnedon or off. That is, a switch is turned on or off to determine whethercurrent flows therethrough or not. Alternatively, a switch has afunction of selecting and changing a current path. Note that the casewhere X and Y are electrically connected includes the case where X and Yare directly connected.

For example, in the case where X and Y are functionally connected, oneor more circuits that enable functional connection between X and Y(e.g., a logic circuit such as an inverter, a NAND circuit, or a NORcircuit; a signal converter circuit such as a D/A converter circuit, anA/D converter circuit, or a gamma correction circuit; a potential levelconverter circuit such as a power supply circuit (e.g., a step-upcircuit or a step-down circuit) or a level shifter circuit for changingthe potential level of a signal; a voltage source; a current source; aswitching circuit; an amplifier circuit such as a circuit that canincrease signal amplitude, the amount of current, or the like, anoperational amplifier, a differential amplifier circuit, a sourcefollower circuit, or a buffer circuit; a signal generation circuit; amemory circuit; or a control circuit) can be connected between X and Y.For example, even if another circuit is provided between X and Y, X andY are regarded as being functionally connected when a signal output fromX is transmitted to Y. Note that the case where X and Y are functionallyconnected includes the case where X and Y are directly connected and thecase where X and Y are electrically connected.

Note that in this specification and the like, an explicit description “Xand Y are electrically connected” means that X and Y are electricallyconnected (i.e., the case where X and Y are connected with anotherelement or another circuit provided therebetween), X and Y arefunctionally connected (i.e., the case where X and Y are functionallyconnected with another circuit provided therebetween), and X and Y aredirectly connected (i.e., the case where X and Y are connected withoutanother element or another circuit provided therebetween). That is, theexplicit description “X and Y are electrically connected” is consideredto be disclosure of the same contents as ones using a simple andexplicit description “X and Y are connected” in this specification andthe like.

For example, any of the following expressions can be used for the casewhere a source (or a first terminal or the like) of a transistor iselectrically connected to X through (or not through) Z1 and a drain (ora second terminal or the like) of the transistor is electricallyconnected to Y through (or not through) Z2, or the case where a source(or a first terminal or the like) of a transistor is directly connectedto one part of Z1 and another part of Z1 is directly connected to Xwhilea drain (or a second terminal or the like) of the transistor is directlyconnected to one part of Z2 and another part of Z2 is directly connectedto Y.

The expressions include, for example, “X, Y, a source (or a firstterminal or the like) of a transistor, and a drain (or a second terminalor the like) of the transistor are electrically connected to each other,and X, the source (or the first terminal or the like) of the transistor,the drain (or the second terminal or the like) of the transistor, and Yare electrically connected to each other in this order”, “a source (or afirst terminal or the like) of a transistor is electrically connected toX, a drain (or a second terminal or the like) of the transistor iselectrically connected to Y, and X, the source (or the first terminal orthe like) of the transistor, the drain (or the second terminal or thelike) of the transistor, and Y are electrically connected to each otherin this order”, and “X is electrically connected to Y through a source(or a first terminal or the like) and a drain (or a second terminal orthe like) of a transistor, and X, the source (or the first terminal orthe like) of the transistor, the drain (or the second terminal or thelike) of the transistor, and Y are provided to be connected in thisorder”. When the connection order in a circuit configuration is definedby an expression similar to the above examples, a source (or a firstterminal or the like) and a drain (or a second terminal or the like) ofa transistor can be distinguished from each other to specify thetechnical scope.

Other examples of the expressions include “a source (or a first terminalor the like) of a transistor is electrically connected to X through atleast a first connection path, the first connection path does notinclude a second connection path, the second connection path is a paththrough the transistor between the source (or the first terminal or thelike) of the transistor and a drain (or a second terminal or the like)of the transistor, Z1 is on the first connection path, the drain (or thesecond terminal or the like) of the transistor is electrically connectedto Y through at least a third connection path, the third connection pathdoes not include the second connection path, and Z2 is on the thirdconnection path”; and “a source (or a first terminal or the like) of atransistor is electrically connected to X through at least Z1 on a firstconnection path, the first connection path does not include a secondconnection path, the second connection path includes a connection paththrough the transistor, a drain (or a second terminal or the like) ofthe transistor is electrically connected to Y through at least Z2 on athird connection path, and the third connection path does not includethe second connection path”. Still another example of the expression is“a source (or a first terminal or the like) of a transistor iselectrically connected to X through at least Z1 on a first electricalpath, the first electrical path does not include a second electricalpath, the second electrical path is an electrical path from the source(or the first terminal or the like) of the transistor to a drain (or asecond terminal or the like) of the transistor, the drain (or the secondterminal or the like) of the transistor is electrically connected to Ythrough at least Z2 on a third electrical path, the third electricalpath does not include a fourth electrical path, and the fourthelectrical path is an electrical path from the drain (or the secondterminal or the like) of the transistor to the source (or the firstterminal or the like) of the transistor”. When the connection path in acircuit structure is defined by an expression similar to the aboveexamples, a source (or a first terminal or the like) and a drain (or asecond terminal or the like) of a transistor can be distinguished fromeach other to specify the technical scope.

Note that these expressions are examples, and there is no limitation onthe expressions. Here, X, Y, Z1, and Z2 each denote an object (e.g., adevice, an element, a circuit, a wiring, an electrode, a terminal, aconductive film, or a layer).

Even when a circuit diagram shows that independent components areelectrically connected to each other, one component sometimes hasfunctions of a plurality of components. For example, when part of awiring also serves as an electrode, one conductive film serves as thewiring and the electrode. Thus, the term “electrical connection” in thisspecification also means such a case where one conductive film hasfunctions of a plurality of components.

This application is based on Japanese Patent Application Serial No.2019-205057 filed with Japan Patent Office on Nov. 12, 2019 and JapanesePatent Application Serial No. 2019-210593 filed with Japan Patent Officeon Nov. 21, 2019, the entire contents of which are hereby incorporatedby reference.

What is claimed is:
 1. A functional panel comprising: a first pixelcomprising: a first element configured to emit light; a color conversionlayer over the first element, the color conversion layer configured toconvert a color of light emitted from the first element into a differentcolor; and a first functional layer between the first element and thecolor conversion layer, wherein the first element comprises galliumnitride, wherein the first functional layer comprises: a firstinsulating film comprising an opening; and a pixel circuit over thefirst insulating film, the pixel circuit comprising a first transistor,wherein the first transistor is electrically connected to the firstelement through the opening, wherein the first insulating film comprisesa region between the pixel circuit and the first element, and whereinthe first transistor comprises a first oxide semiconductor film.
 2. Thefunctional panel according to claim 1, further comprising: a regioncomprising a first group of pixel sets and a second group of pixel sets,wherein the first group of pixel sets is arranged in a row direction,wherein one of the first group of pixel sets is electrically connectedto a first conductive film, wherein the second group of pixel sets isarranged in a column direction intersecting the row direction, andwherein one of the second group of pixel sets is electrically connectedto a second conductive film.
 3. A display device comprising: a controlunit; and the functional panel according to claim 1, wherein the controlunit is configured to be supplied with image data and control data,wherein the control unit is configured to generate an image signal fromthe image data, wherein the control unit is configured to generate acontrol signal from the control data, wherein the control unit isconfigured to supply the image signal and the control signal, whereinthe functional panel is configured to be supplied with the image signaland the control signal, and wherein the first pixel performs display bythe image signal.
 4. An input/output device comprising: an input unitcomprising a sensing region; and a display unit comprising thefunctional panel according claim 1, wherein the input unit is configuredto sense an object approaching the sensing region, and wherein thesensing region and the pixel set overlap each other.
 5. A dataprocessing device comprising: an arithmetic device; and an input/outputdevice, wherein the arithmetic device is configured to be supplied withinput data or sensing data, wherein the arithmetic device is configuredto generate control data and image data from the input data or thesensing data, wherein the arithmetic device is configured to supply thecontrol data and the image data, wherein the input/output device isconfigured to supply the input data and the sensing data, wherein theinput/output device is configured to be supplied with the control dataand the image data, wherein the input/output device comprises: a displayunit configured to display the image data by the control data; an inputunit configured to generate the input data; and a sensor unit configuredto generate the sensing data, and wherein the display unit comprises thefunctional panel according to claim
 1. 6. A data processing devicecomprising: at least one of a keyboard, a hardware button, a pointingdevice, a touch sensor, an illuminance sensor, an imaging device, anaudio input device, an eye-gaze input device, and an attitude detectiondevice; and the functional panel according to claim
 1. 7. A functionalpanel comprising: a first pixel comprising: a first element configuredto emit light; and a first functional layer, wherein the first elementcomprises a first electrode, a second electrode, and a layer containinga light-emitting material between the first electrode and the secondelectrode, wherein the layer containing a light-emitting materialcomprises gallium nitride, wherein the first functional layer comprises:a first insulating film comprising an opening; and a pixel circuit overthe first insulating film, the pixel circuit comprising a firsttransistor, wherein the first transistor is electrically connected tothe first electrode through the opening, wherein the first insulatingfilm comprises a region between the pixel circuit and the first element,and wherein the first transistor comprises a first oxide semiconductorfilm.
 8. The functional panel according to claim 7, wherein the firstinsulating film comprises a second insulating film and a thirdinsulating film, wherein the second insulating film comprises a regionwhere the third insulating film is positioned between the firsttransistor and the second insulating film, wherein the second insulatingfilm comprises silicon and oxygen, and wherein the third insulating filmcomprises silicon and nitrogen.
 9. The functional panel according toclaim 7, further comprising: a pixel set comprising; the first pixel;and a second pixel comprising a second element, wherein the firstinsulating film comprises a fourth insulating film, and wherein thefourth insulating film is configured to isolate the second element fromthe first element.
 10. The functional panel according to claim 7,further comprising a first driver circuit, wherein the first functionallayer comprises the first driver circuit, wherein the first drivercircuit comprises a second transistor, wherein the second transistorcomprises a second oxide semiconductor film, and wherein the secondoxide semiconductor film comprises an element contained in the firstoxide semiconductor film.
 11. The functional panel according to claim 9,further comprising a second functional layer, wherein the secondfunctional layer comprises a first contact, a second driver circuit, anda fifth insulating film, wherein the first contact is electricallyconnected to the second driver circuit, wherein the second drivercircuit comprises a third transistor, wherein the third transistorcomprises a semiconductor comprising a Group 14 element, wherein thefirst functional layer comprises a sixth insulating film and a secondcontact, wherein the sixth insulating film comprises a region betweenthe fourth insulating film and the fifth insulating film, wherein thesixth insulating film comprises a region bonded to the fifth insulatingfilm, wherein the second contact is electrically connected to the firstcontact, and wherein the second contact is electrically connected to thepixel circuit.
 12. The functional panel according to claim 9, whereinthe second pixel is configured to perform display using light emittedfrom the second element, wherein the second element is configured toemit light of the same color as light emitted from the first element,wherein the first pixel comprises a color conversion layer, and whereinthe color conversion layer is configured to convert the color of thelight emitted from the first element into a different color.
 13. Thefunctional panel according to claim 7, further comprising: a regioncomprising a first group of pixel sets and a second group of pixel sets,wherein the first group of pixel sets is arranged in a row direction,wherein one of the first group of pixel sets is electrically connectedto a first conductive film, wherein the second group of pixel sets isarranged in a column direction intersecting the row direction, andwherein one of the second group of pixel sets is electrically connectedto a second conductive film.
 14. A display device comprising: a controlunit; and the functional panel according to claim 7, wherein the controlunit is configured to be supplied with image data and control data,wherein the control unit is configured to generate an image signal fromthe image data, wherein the control unit is configured to generate acontrol signal from the control data, wherein the control unit isconfigured to supply the image signal and the control signal, whereinthe functional panel is configured to be supplied with the image signaland the control signal, and wherein the first pixel performs display bythe image signal.
 15. An input/output device comprising: an input unitcomprising a sensing region; and a display unit comprising thefunctional panel according claim 7, wherein the input unit is configuredto sense an object approaching the sensing region, and wherein thesensing region and the pixel set overlap each other.
 16. A dataprocessing device comprising: an arithmetic device; and an input/outputdevice, wherein the arithmetic device is configured to be supplied withinput data or sensing data, wherein the arithmetic device is configuredto generate control data and image data from the input data or thesensing data, wherein the arithmetic device is configured to supply thecontrol data and the image data, wherein the input/output device isconfigured to supply the input data and the sensing data, wherein theinput/output device is configured to be supplied with the control dataand the image data, wherein the input/output device comprises: a displayunit configured to display the image data by the control data; an inputunit configured to generate the input data; and a sensor unit configuredto generate the sensing data, and wherein the display unit comprises thefunctional panel according to claim
 7. 17. A data processing devicecomprising: at least one of a keyboard, a hardware button, a pointingdevice, a touch sensor, an illuminance sensor, an imaging device, anaudio input device, an eye-gaze input device, and an attitude detectiondevice; and the functional panel according to claim 7.